Thanks all. Besides the other things I've already mentioned, I anticipated HfAndy's advice and have learned to drink right-handed (which wasn't much of a trick since I am right-handed anyway!)

Nope, there are no signs of any manner of infection. Thank goodness! I worked in hospitals (including the ER,) for long enough to recognize all manner of dangerous symptoms.

Early on, I thought about the kind of injury RichM described. I've had the same sort of thing happen in much the same way or by carrying one too many buckets of water.

The fact is, lately I've been playing guitar far more regularly than in almost any other time in my life. Heck, I've even developed calluses on my fingerpicking fingers! So, I imagine that Bonnie is probably very close to the truth when she suggested some sort of injury due to repetition. My overall suspicion is that the callus formed to protect the vein from the pressure I was puttting on it so often by playing barre chords repeatedly - especially in one particular song I've been practicing lately. Taking that theory one step further, I believe the callus grew to the point at which it was putting unusual pressure on a nerve.

I do have plans to visit the doctor in the next few days. However, I have some doubt that I will receive specific help. I remember during my first visit, this doctor was quite puzzled by the calluses on the tips of the fingers of my left hand. Clearly, she had never played guitar or knew anyone who did.