I totally agree with what you're saying. I noticed the same thing with maths and sports. I used to be really bad at both, or at least told myself I was and would never improve in any of them. After a while my focus started to shift and I just gave it a try- turns out math can be fun and by now I work out regularily to destress. I feel like sometimes you just need to tell your mind to stop and just do whatever you feel you can't do to prove it wrong ;). We really are our worst enemies sometimes, haha