venting?

Idk what to do. So a few months ago i started going to therapy and was instantly diagnosed with social anxiety which makes sense. The reason i started going to therapy in the first place was because i used to sh. So yea. But i felt like social anxiety wasn't the only thing that's wrong with me. Idk but i have these problems with making friends cause when i am for an example next to someone i know, i just don't know what to talk about. Idk what people talk about and i waste so much energy on just basic conversations. Because of that i have like one best friend and some other "friends" that i occasionally talk to in class or sth. I hate that because in summer or on holidays, weekends, etc. everyone hangs out with their friends and i'm at home in my room. Don't get me wrong i like being alone and doing things on my own like reading or crocheting but i also sometimes want to hang out with friends, go somewhere or whatever. And the worst thing is when i ask my best friend if she wants to hang out and she says that she's with someone else. Idk why (i mean mybe i do but idk) i get jealous when my best friend or specifically my aunt talk to someone else or hang out with someone else especially when i want to hang out with them. They are my "favorite people". I've been saying that for at least two years now only to find out that people with bpd have favorite person/people. And yeah basically i think i have bpd i mean i already did tons of research and i relate to many symptoms but idk what to do. I've been to like 4 or 5 sessions with my therapist and i'm scared to open up so it will be hard for her to diagnose me with anything else. I was thinking about bringing it up on my next session or sth but idk i don't want to seem dramatic or like im overreacting. If anyone reads this please tell me what should i do.

P.S. 

I asked my mom today when will I go to my next session and she told me that she will call my therapist even though she doesn't see a reason why should i go to therapy when i'm so sociable and i seem fine. And yeah she says that she knows me VERY well. Yeah right.