Red, Sensitive Penile Glans After Unprotected Sex, Burning Sensation After Urination, Soreness In Testicles. Reason?

What would cause the penile glans to turn red and sensitive only hours after unprotected sex? It has stayed sensitive for 48hrs followed by an uncomfortable light burning feeling after urination , but not during. Also there is a clear drainage but I believe it is urine because it happens most within an hour after using the bathroom. Some soreness in the testicals, and an occasional pinching feeling in the urethra mostly near the meatus, but can also be lower. I have been urinating more frequently than usual, but with normal flow. Background is; I m 25, I work out 5-6 times a week and eat paleo. I also take a number of supplements like whey protein , multi- vitamins , and multi-minerals. I will say I drink a lot of caffeine though. Today I have had 2 monster energy drinks (Splenda, no sugar), a double shot espresso redeye, and another cup of coffee.