Today I scratched what seemed to be a rather large (not very raised, but large in area) bug bite on my leg (upper thigh). I looked at it, and other than the raised area there was nothing going on -- I didn t remember getting bit, but I assumed it was a bug bite. This evening, I realized that the same area is now sporting a very large, very colorful bruise , and the raised area seems to have left. What might cause this? Could it have been a clot?