I ended up taking a break for a few days due to circumstance, and the problems in my legs went away, so there was that.
I'm actually on a singlespeed right now. It works fine for most things, though I have come to decide that I need to get around the fast route, as it was trying to pound my way through it that made my legs so sore in the first place. I'll see if I can find a better route this weekend.