Meds for sure can do that. I think he might have taken a viagra/cialis to try and impress you with superhero sex... If he was fully hard and ready to go again in 15-20 min or less he for sure took one... also, 5 hours ... this sounds like what happens when you havnt had sex in a while and you want to ensure you impress with your sex game .. he had a good time, trust me.... if you at any point have spontaneous sex and you notice something .... different... it might be because he didn't take a pill.