It’s not possible to determine a diagnosis over the Internet. The other issue is your age. Some mental health professionals are reluctant to diagnose teenagers with a mental illness because it is a turbulent time, both developmentally and emotionally.
When mental health problems are a concern, it is especially important to refrain from using drugs and alcohol. They can negatively impact your mood and personality. They could make your symptoms worse or perhaps may even be causing them. Therefore it would be in your best interest to stop using drugs and alcohol.
It was your opinion that you don’t possess a “unique personality ” and that you are a conglomeration of a “bunch of stolen identities.” What I think you might mean is that you are behaving in ways that you believe other people want you to instead of just being yourself. That could stem from low self-esteem.
Lack of self-esteem might also be evidenced by your “hooking up with guys [you] don’t care about.” You might not be so willing to indiscriminately “hook up” with these people if you felt better about yourself.
You have received different diagnoses. This would suggest that you have been evaluated by a mental health clinician. It’s good that you were in contact with mental health professionals, but you did not mention being in treatment. Counseling is the ideal treatment for the problems you have described. Medication could also help with your symptoms.
Erik Erikson is a famous and well-accepted developmental theorist. He talks about a stage that people go through when growing up. It is called identity vs. identity confusion. In essence he is saying that a teenager must go through a stage where they will find out who they are. They need to find their identity. You can read about this and see if it explains some of your feelings.
The symptoms you described require treatment. Contact a mental health professional and ask for his or her assistance. What’s most important is treating your symptoms with counseling and if necessary, medication. Please take care.
Dr. Kristina Randle