dry splotchy skin on penis

Im 20 years old and recently have developed dry splotchy skin on the shaft of my penis and a little on the four head and just under neath the four head. It gets really dry then the skin cracks a little no discharge but i can tell that the skin has cracked. Iv been sexually active with my girlfriend for about 5 months now and we started to not use condoms about the second month into our relationship. She hasn't noticed any of my symptoms but im really nervous because i don't know if what i have is caused by irritation in sex or some kind of std. the splotches usually go away about a week after they appear but when i have sex they reoccur can anyone tell me anything of what this might be? thank you

[Vance2335]

Does not sound like a STD, but you can see a Dr for proper diagnosis. Sounds like common dry skin or maybe irritation.