My training session tonight was 100% upper body (outside of a set of squats with lower weight than usual), and my calf was feeling back to normal afterwords. It felt so good that I did take my Trek to a local park and just spun easy (between 12-13mph) on flat roads only for 30 minutes. No twinges or anything.

Now that I have slowed down and rested a little since then, some tightness is returning, but I am no longer concerned that there is any real damage. I will go to spinning class tomorrow and not hit it as hard as normal, then try a real ride on Friday.

Thanks for all of the tips - and I will try rolling it again before going to work tomorrow morn. if I wake up with it still sore.