[Epona]

Probably you had bumped yourself the previous day and your leg was sore which caused you to have the dream. Dreams which seem to take hours only take place over a matter of seconds or minutes at most, and this was just a reaction to your leg hurting, nothing more sinister than that.

I once had a horrible dream that my leg was being operated on without anaesthetic. It was very vivid and painful, and I woke up to find I had a cramp in my calf muscle! No big deal, sometimes if the phone rings or an alarm goes off it gets incorporated into your dreams, same with pain.