Of course it’s possible that you have a personality disorder. It’s equally possible that you are a normal teen who is trying to figure out who she is and how to be with others. The problem with diagnosing personality disorders during the teen years is that it is perfectly normal for teens to have characteristics of all or some of the disorders while growing out of childhood and into the adult person they will be.
A personality disorder is an inflexible and enduring set of characteristics. An unhealthy pattern of thinking, functioning and behaving causes a person with a personality disorder to have trouble perceiving situations accurately and relating appropriately to other people.
The way to find out is not through an advice column. You are concerned enough about yourself to write to us so I hope you will get the help you need to answer your questions. I hope you can find a mental health counselor who can do a thorough assessment. If you are a normally stressed teen, you will find out which will give you peace of mind. If you do have the makings of a personality disorder, you will be given that information along with a treatment plan for how to address it.
I hope you will get such an assessment to answer your question. It must feel terrible to be always wondering about yourself.
I wish you well.