Five days ago I jumped off a tree from a fairly short distance, little under 6ft.  I had a few beers and really needed to pee. When I hit the floor I felt a sting on my penis. A day later I noticed a large-ish (maybe half an inch), red and hardened bump in the middle of the shaft. I've never had an STD/STI or had had sex anytime recently before or after that, so I want to believe this is a lymphocele. Could it be anything else and should I be worried?