I think worrying about what T thinks of you, and wondering if you are believed by them, is a very normal concern. Lots of people worry about these issues.
It is also very possible that the contradictions you are aware of are a result of dissociation. For instance, high anxiety all the time may be very true for one part, while not true at all for another. Your T believes you dissociate, so will be able to understand how this may be true. It is also possible that you have a different perspective on different days. For instance, if you go in feeling really down one day, you may express that you are constantly miserable. You may go in on another day when you are feeling much happier, and express that you've been feeling generally good. It's not lying, it's just having different perspectives based on how you're feeling. T should be very familiar with this. Sometimes too, you may just genuinely forget things. Memory is far from perfect. You might tell T that something hasn't happened in years, then have your memory jogged by reviewing your journal entries, and realize it's been more recent than that. This doesn't mean you lied, just that you were mistaken. I am certain T could understand this.
Have you told T about the fuzzy feeling you get in your head while you're there? This could be related to dissociation.
Granted, I don't know you at all in real life, but everything I know about you from PC tells me that you work hard, and genuinely want to get better. I am confident that your T would be able to see this as well.