the second your arms start to hurt, stop playing.
jim has good ideas.
i might suggest longer than three days. take a couple weeks off, seriously. listen to some music–work on your ear instead of your playing. if you devote the same amount of time on your ear as you do your playing, you will find a great improvement when you pick up your instrument. i had a lot of problems for a while, so i stopped playing for a couple months, and when i picked up my instruments again, i had a better, musical perspective.
i often find that tendon problems are posture problems as well as grip problems. if your posture is adding too much stress on your upper body when you play, that will translate to extra pressure in your tendons. i find working on my posture through yoga, pilates, running, or general exercise helps the tenseness in my upper body and arms. i find by having a better core you can fix a lot of upper body problems, especially after giving your upper body time to recover and loosen up.
one good suggestion is i have been given was to put your hands down at your sides, keep your hands relaxed, and try to replicate that finger position with your flute.
i have no authority on this, but i would bet t hat people with rss who never recover never radically change their posture, walking habits, how they use their upper arms, and how they use their necks. i would suspect that they just try to change how they use their wrists.
i try to do wrist stretches, such as they do in martial arts, as i find it helps when i am putting too much pressure on my tendons. i would say to be careful with these, though, because i dont know a lot about them and was shown how to do them by someone who knew what they were doing.
also, in addition to the icing you already are doing, i would say steaming hot baths help relax tense muscles. as you have kids, it would also be a good idea for your nerves!