I play clarinet and piano and suffer from hand and wrist issues. Playing for even 15 minutes causes pain in wrist (and thumb for clarinet) thoughts?

Tendinitis . With your history , age and location of pain ( wrist and thumb) the most likely diagnosis is tendinitis ( specifically deQuervain's tendinitis).This is the most common tendinitis of the hand and involves the thumb extensor tendon.A physical exam by an ORS would confirm. Ibuprofen, bracing, ice massage and rest usually help. A well- placed injection can be helpful . Best of Luck!