Quick update.  After swimming yesterday, I also did a quick workout with Terri where we did interval stations and the ended by doing 30 second sprints (4 total) with 2 minute rest between sprints.  I did not think much of it at the time, because I took most of it easy except for the sprints.  However, as Saturday afternoon rolled in, and all day today, the very top of my thigh (level with my hip) is very, very, very sore.  I have tried to stretch it all day today, but it is the strangest place to have a sore muscle. 
I did make it to the Y today.  Rode the exercise bike for 4 miles, ran 3 miles and lifted weights (biceps and triceps).  I felt fine once I was all finished.  But it is amazing how it sets in once you hit the couch.  The longer I am planted on the couch, the more difficult it becomes to move.