Mental health diagnosis?

i am a 16 year old female. this is going to sound like a stupid question but i am at the end of my rope. i have emotional problems but i am not sure why. my doctors are puzzled also. when i was 12 i started self injuring and i am not sure why. then i started using drugs like weed, vicodin, and my favorite, cocaine. i also have eating disorder problems. i am a negative person and do not see the point in life. ive been in many hospitals because i have actively been suicidal and have self injured to the point of needing stitches on several occasions. my "official" diagnosis is bipolar type 2 but im not so sure of that. i have no history of abuse and i have a great life. i am just emotionally retarded. none of the antidepressant/mood stabilizing drugs have helped me and i have tried a lot of them. i am in talking therapy. i have started RTMS therapy (sort of like ECT) and i am taking wellbutrin (secretly just for weight loss) but now i am becoming paranoid and having manic moments. i do not self injure for the usual reasons. a lot of the time i self injure when i am happy and i just like the adrenaline rush and seeing how far i can push myself. i do not see a major problem in my thinking. i cant deal with myself anymore though. i have put everyone around me through hell and i have a lot of guilt because of that. i also have headaches, memory problems, and my pupils are usually abnormally dilated. my question to anyone out there is, what do you think is wrong with me, and what do you think i should do from here on out. personal stories are welcomed and appreciated. Thanks