I have noticed a reduction in the size of my balls and also a decreased amount of sperm. Sometimes a couple times of ejaculating will cause my penis to feel like it is burning on the inside of it. It is like the muscle that releases the sperm gets sore and so do my balls. I have noticed a decrease in penis size as a result of the decrease in size of my testicles.
Before october I had no trouble at all with any of this.

I noticed that it burned when I urinated back in october and went and got tested for std's. I also had a red rash around the outer rim of my penis head. It wasn't very big but is actuallys till there. They dismissed it and my tests came back negative. I still wondered about the rash and a couple months later the above started happening with the reduction of ball size. I got the bill for the first doctor and it was high as hell. So that stopped me from going back for awhile. I ended up going back and getting tested at the public health center and my tests came back negative as well.

The first doctor visit they gave me a shot.
The 2nd, I got some erthromyician andanother drug. My understanding is that I was treated for ngu and urethitis. Anyway... I am wondering where to go from here and can't really afford to throw alot more money away without some idea what is going on.

Should my sex drive die like that? I'm a 21 year old male who isn't really highly stressed out or really unhealthy. I exercise a few times a week etc.

Any ideas?