I think I've finally done it this time guys. I have been unable to play for about 2 weeks now, but the good news is I'm going to my chiropractor on Monday.
Ive played guitar for many years now, but I started playing bass about 2 weeks ago (picked up a cheap washburn xb100 from craigslist) and I just went to town on it, which in hindsight was really really stupid. The action on this bass was ridiculously high and still is after lowering it to the max without fret buzz. I was belting out all my scales and stupidly I kept playing when I felt pain, though I naively believed I was developing my strength. Well, long story short, I strained the crap out of my left hand, wrist and forearm. Almost all of my pain is back in the forearm tendons, bottom part of the arm near the elbow. If I play for more than 15 minutes it feels like fire ants are biting the soft part of my forearm and the area gets warm to the touch. I believe this is a classic case of tendonitis, but I my doctor will tell me for sure. In the meantime it is beyond frustrating to not be able to play your instrument after a hard days work, it's something I look forward to now. Hope this clears up soon.