Am I Nuts?

So I seem to finally be injury free.  I've had a good couple of training weeks, including an epic 15 miler in San Francisco last weekend.  This weekend I got in a couple of long workouts including some swimming, biking and running, and this morning I had a nice run in East Rock Park, the last of my New Haven runs, as the semester winds down.  The crazy part, though is that I'm signed up for a sprint tri this weekend in South Jersey.  I'm not going to be fast, but I'm comfortable with being able to complete the distance (1/2 mile swim, 20 mile bike, 4 mile run).  The part that has me nervous is the swim.  It has been cold, cold, cold here all April.  I'm expecting 50 degree water, and even with a wetsuit that's going to be unpleasant . . . Wish me luck!!