What Causes Sore Penis After An Intercourse?

Good Afternoon bit embassaring i have not had sex for about 18 months and last week end well gues what and now my penis is very sore and its got blotches and spots and i am panicking now i am hoping it is frush that i have got and not any thing more serious (as far as i now my partner has not had sex for about 2 months and before that a year.