It's normal, I would just say you should try to stop beating yourself up about it. Maybe start by talking about how hard it is to talk? Trust is a process that takes time. I'm 2 years into therapy and in my 30's and still uncomfortable, and I've found that I get more comfortable the older I get, at your age I would have been totally mute . When I really want to say something to my therapist but I just cant, I put it in a letter and give it to him. Also, a lot of sessions you won't notice a benefit immediately, and maybe not all of them do benefit you I don't know, but I think for me the process has been very gradual, and only looking back on where I started to where I am today do I really see the big change.