My left testy is like receding up into somewhere almost 90-10% every time i sex. Its like my ball sack( sorry dont know medical terms) is getting smaller and and i only have one testicle. It doesnt hurt and goes back down to normal as soon as i ejaculate. I have already had a hernia surgery a couple years ago. Im 20 years old. I started noticing it a few weeks ago but i havent down anything strenuous to cause another if my memory proves right. It only happens when in sexual intercourse or maybe when im sexually aroused but dont put my hands down my pants every time to check. I have sex steadily( almost everyday or every other day.