numb and pain in testicle

I am 28 years old and I often experience numbness in my right testicle this can happen after sitting down and also after ejaculating! I have examined this testicle and have noticed a small growth probably the size of half a grain of rice, so very small- if i touch this or the testicle itself i get a pain that generally starts from my testicle and goes up towards my stomach. My sperm tends to be very watery aswell although i have read this happens? Upon experimentation of my left testicle i would self diagnose myself off having a slight variocele aswell. thanks