Well my girlfriend was performing oral sex on me and she said that noticed a different smell on my penis. Then one day i was masterbating and i smelled the sperm and it did have a different smell to it, an odd smell. Its not too bad and the sperm looks normal just doesn't have the usual "chlorine kinda smell". And another thing, for the past couple of years i have gained a significant amount of weight (110 to 175lbs in 2 yrs.) and now i am experiencing fluid in my anal area. Its very uncomfortable. I was wondering if it was just sweat due to my weight gain. Can anyone help. I dont sleep around or anything, so i doubt its some sort of STD but im still a little worried.