I don't know how much help I can be to you... but I feel I know how you feel. I read through your post and felt like, at points, I was reading about what I was feeling around my grammar school and high school years and even now. I myself suffer through panic attacks quiet frequently, most of them ending with me throwing up as well. I do not know how long your attacks last, because everyone is different and a panic attack can last 4 hours for some and last only 20 minutes for others. And I've just recently stopped self harming myself, it's going to 3 years in exactly a month today. I cut in the same areas you are now harming but I did other things to hurt myself. I understand that it is the only thing that seems to help. For me, it helped me feel like I was actually there, not an emptiness that just watches everyone else's life be lived. It was my minds way of understanding that I was alive. That I can feel something.
The advice I can give you is to, one, sit your parents down. Ask them, both, to give you the time and the patience from them that you need to explain your feelings to them. If they CANNOT promise to sit QUIETLY and CALMLY, you do not tell them how you feel. They need to be quiet and calm while you speak and, most importantly, they need to listen to you. I do not know what kind of people your parents are. You might have better luck writing all of your emotions down in a letter, one for each of them, and giving it to them to read, like I did with my parents when I wanted help. But YOU need to want their help. You need to be comfortable enough to try to explain to them how you feel, what is constantly going on through your mind. There is no point in going to a psychiatric ward when you are not willing to get better. It WILL make you feel worse then you already do. This is the opposite of what you want, what anyone feeling like this, would want.
Two, get rid of everything you use to cut yourself. This is the hardest step and is almost impossible to do when you are alone, so I suggest doing this with your parents once they calmly understand that you want the help and they understand the difficulty for you to ask them for help; that you can admit that you can't do it on your own. You have to take it slow and breath while taking EVERY blade or sharp instrument and putting it into a bag or basket. Once every stash of yours is empty (If you have more then one place to hide your blades) you give them to you parents and you have to let them dispose of them without you seeing. Leave the house, sit in the bathroom, put headphones on and blindfold yourself, but you cannot know where the blades are going. And once they are gone, find things to do during your urges. Learn to play an instrument, read books, go walking, crochet hats or scarves or write. ANYTHING to keep your mind busy helps. things that can frustrate you, challenge you to do better help as well. Even giving yourself a challenge to do while watching a tv show helps.
Third, go to a new therapist. Do the research yourself on the possible person. Now and days everyone writes a review so find them and read. If, out of ten reviews, more then 3 people dislike said person, move on. A therapist is there for you to express your emotions, your thoughts, your troubles and your problems too without having them take a side. They are a third party, a person to vent to. But not all enjoy their jobs and would prefer to hand off patients to a psychiatrist to give them medication, when the person might not need the medication. You need someone who will sit there quietly and LISTEN to you. Your psychiatrist, talk to them about how the medication makes you feel. Explain it to them in detail. Tell them everything that happens when you take them and then ask for something that won't make you feel that way. They are there to help, but it's not their fault that the medications react one way with a persons body. That is why you talk to them and they change the medication until you feel better. It's a long process and it is painful, but the moment the medication actually works like it is supposed to, you really do feel better. But if you do not trust that doctor, I would also change them and do your own research for the next one.
And lastly, sometimes a stranger you see face to face once, twice, three times a week, is not enough. Having someone who you can call a friend is important, but it is not the most important thing. That person was never your friend. Someone who suddenly starts bullying does so because it has either been on their mind the whole time they've known you and they finally do it because they got board with being nice or has changed and now finds treating others like crap, fun. Sometimes, but rarely, it is because they themselves are being abused but that's not always the case. Be patient and quiet. There is a line, from a poem I found in an old journal years ago, that I now I live by, "Sit quiet and silent, patient and observant. Do this and the world will give up the secrets you deserve; the secrets you desire." I always interpreted this as, if I am quiet and observant, I will learn more about the people around me to choose who I want to let into my life. You can do this too. There are decent people in this world and they will find their way to you, you just have to be patient and careful in the mean time. But do not let your heart become cold and uncaring. Because you only hurt yourself and anyone else who actually cares for you, like I had done.
It may sound cheesy... but with time, everything will get better... but you have to make it so. Be happy but be strong. Work for your happiness... even if you feel like ending it all would be so much easier... it will only prove to everyone who pushed you to that point that you were weak. They will pity you and feel sorry for you, but, as harsh as it sounds, they will forget you, because you gave up. Nothing in life comes easy. Happiness is one of these things... and you will have to work hard to get even a small amount of it.
But you have to realize... everyone deserves to be happy... everyone deserves at least happiness... even the people who are so broken inside that being happy makes them feel guilty, even they have to realize that THEY deserve happiness. WE deserve happiness. We deserve to feel better. We deserve to live and no one can put a price on our life but ourselves.
I hope my words encourage you... or even just help you know you are not alone and I am always willing to talk if you need someone to talk with in those rough times.
-hugs you tight- <3