Neverending wrist pain

I have had wrist pain since like 2 months and I dont know why because i've done nothing to cause it. I have been xrayed and checked by 2 different physical therapists and a doctor and there is no fracture in my wrist, obviously since i've not injured myself! I've had a bruise on my hand that's all, that bruise fades and then comes back randomly.
My wrist doesn't hurt constantly. All of a sudden though I twist my arm in a certain way when picking something up or gripping something and the pain hits and I have to wear my wrist brace. The wrist brace makes the pain to go away as long as I wear it. The only trigger I can think of is my internship in a library. I started that internship in November and it ended a month ago this week, however I just got employment there so i'm going to start working there soon parttime. It's a big deal for me, i'm neurodiverse and have been unemployed since like forever and I love working in a library and my boss and co-workers are amazing hence it's not even on the map that I would turn it down.
I've been home for a month though and my wrist is still not better? In fact two days ago it got much worse again just because I reached for something on the top shelf in the store, and it wasnt something heavy in the slightest... It was the gripping that triggered my pain and now it's really bad all the time again. My physical therapist suspects an overworked muscle but I feel like it would've gotten better by now, plus I use my left hand just as much when i'm working and that one is fine? My mother thinks the physical therapist is dumb because I obviously have arthritis, because that's what she suffers from and it is genetic. My aunt also has it and my grandmother had it but i've been told by a doctor that I cant suffer from arthritis because my fingers arent crooked. What else could it be? Is it really possible to have an overworked muscle thats so badly overworked it doesnt get ANY better even though i've been really careful ?! I did get exercises from my physical therapist but I cannot do them it hurts too much. Lifting my cat hurts too which is a shame but I still do it lol. It doesnt hurt all the time some days i'm completely fine so it's weird.