I decided to go to the gym last night after work, to give my legs more of a rest from Monday morning's workout. After some cardio, I tried a weight machine for legs for the first time in ages, but felt some sharp pain in my left leg, so I tried some one-leg lunges instead. I didn't feel any sharp pain doing those, so I'll stick with those for a little while.
I did some upper body strength training after that, and followed with a good stretch/flexibility session on the floor. A hot bath with Epsom Salt felt great afterward!