I had a similar experience at the exact same age. Mine was a speech block (I would just get stuck mid-sentence). It came out of nowhere and sabotaged my life for a couple of years. I actually discovered John Harrison’s articles at the time (this was back in 2006-07), when I was desperately looking for answers. I found his work interesting, but it didn’t fix the problem just by reading it. I eventually did a few phone consultations with him personally, and he told me something that practically fixed the problem overnight. The gist of it was, I was still thinking of myself as a scared little child in a world of big, scary grownups (I had recently started a new career at the time, and I legitimately was intimidated by a lot of people and things I didn’t know... I felt like a minnow in an ocean of scary sea monsters). This total lack of confidence was manifesting itself as speaking difficulties, which then compounded the problem even worse... but I never could’ve drawn the correlation on my own, because my lack of confidence seemed so disconnected from my ability to speak coherently. Sure enough though, once he pointed it out for me, it became much easier to understand how one issue led to the other. I began to focus on the areas where I did feel confident and worthy, and I started intentionally thinking of myself as an adult among other adults (one who was a peer, not a subordinate) which went a long way toward overcoming the problems. I still have the rare speaking issue from time to time these days, but the difference is, I don’t care much about it anymore. Especially when I see other very confident and successful people who stumble over their words and keep going without another thought, I choose to do the same thing. The issue really was 100% in my head, the trick was to unscramble the puzzle and understand what the real problem was. Easier said than done, but you can do it!