Rehab from an injury, or in Red's case surgery, is never a straight line - it's often like one step forward, two steps back. Yesterday, Red was completely and wonderfully sound for his 5 minutes of trot work. Today, not so much. His "offness" was very slight, almost not there - but there. He was perfectly happy to trot, though, so it didn't seem to bother him much. Could it be the work from yesterday (stressing the leg)? Could it be muscle soreness from not having worked for more than a month? Could it be the farrier handling his leg this morning to give him his trim? Who knows?
Anyhow, I called and left a message for my vet, saying that I was going to go back to doing only walk rides over the weekend and then see how his trot felt on Monday. The fact that he was completely sound yesterday probably means that there is no underlying soft tissue injury to be concerned about. It's likely that there are adhesions breaking up, and some soreness relating to that, as well as muscle soreness relating to coming back into work. But taking it slowly isn't going to hurt things in the long run - his full recovery might be delayed a bit but that's OK with me. I slathered on some Sore-No-More (mostly arnica, good for swelling/inflammation), and he appreciated the rubbing and massage.
One step forward, two steps back - that's rehab!