What makes me think this isn't tendenitus though is that it never happened before when I played WAYY harder and more often, and all of a sudden I picked it up after a few days absence, tried to shred a bit, and found my arm tensing up. I can still play fast and it doesn't hurt or anything, it's just that when I attempt to do things that came easy before, it tenses up now. Wierd....
I suppose I should consider the fact that I have tendenitus again, this time in my upper arm/elbow, but I'd rather not face that right now...