some time i feel a slight pain in on of my balls left or right .... irregular contraction and relaxing of scrotum for example somtime when i feel hot my balls do not relax and some time when feel hot my balls contract .... by the way i have undescended testicle i did a surgical operation to get it down 8 years ago and it was successfull .... i am 26 years old .. my sexual desire is very strong and i have no problem in practicing sex ...