I was able to go swimming tonight. Hooray! After a week of taking anti-inflammatories regularly (ie, when I remembered), I swam without really hurting my arm. There was some popping going on, and after I was done, my arm felt stiff. However, I'm icing it now, and I think I should be A-OK.
I'm so relieved. This looks like a relatively minor problem after all. I had these scary visions last week of never really being able to swim again. Because I can be a little fatalistic like that.
My times were way off, but I was trying to take it easy.