So I've been dealing with anxiety for a while but I have this side effect and didn't know if I can attribute it to anxiety or something else.

So whenever I work on something, home renovations, job that involved counting or thinking, etc... I always felt that I'm not doing the task correctly. I had this job many years ago were I had to tally up all the money from the register and account for receipts and payments/charges on customer accounts and despite me doing the job for several weeks I felt like I was doing it wrong every day. I still don't know if I was doing it correctly but the owner never said anything so I assume maybe I was.

Another example is I was tiling a shower and I had pre cut 3 tiles and fitted them together to ensure they fit correctly. When I made sure everything fit right I pulled them off, put mortar on them and couldn't for the life of me figure out how they went back together, despite only being 3 tiles. I got really tired of thinking how they went up on the wall so I ended up just tiling them however. It later became apparent that I did it incorrectly and tiled them backwards, completely opposite of how they should've went in.

It seems that the longer I think about something the more confusing the task becomes and my head just spins so I quickly move on to the next task. Studying in especially hard since if I don't understand a topic after a while I'll have to jump to another topic, and of course the topic I skipped is always what ended up being on the exams.