Well... I doubt you're stupid. Actually I can relate to quite a bit of this. This is part of the reason I'm pretty-much a recluse in real life but active here on PC. Of course I'm old too... so that's also part of my problem nowadays. But, to a large extent, I've always had similar problems. It's just getting worse as I age. (By the way, I always sucked at math too!) I've never had any psychological testing of any consequence or been formally diagnosed with anything. But I know I've struggled with serious levels of anxiety my entire life; & I presume that perhaps has been at least some of the cause of my own problems.

Here are links to 6 articles, from PsychCentral's archives, on the subject of how to raise your self-esteem, the first by our host Dr. John Grohol, Psy.D.:

6 Tips to Improve Your Self-Esteem

7 Tips to Raise Your Self-Esteem and Keep It There

10 Ways to Increase Self-Esteem | Cultivating Contentment & Happiness

3 Ways to Cultivate Genuine Self-Esteem

Self-Esteem Struggles and Strategies That Can Help

https://psychcentral.com/lib/the-sel...ula-for-women/

You mentioned you've never been diagnosed with anything other than OCD. One other thought would be to take some of the quizzes & tests that are on offer here on PC. Here's a link to the listing of quizzes & tests that are available:

https://psychcentral.com/quizzes/

My best wishes to you...