I'm 17 yrs old and for the past 4 months I've been having non-painful spasms in my left testicle. They only happen when I'm lying down and sometimes sitting. I've also noticed a lot of tightness and discomfort in the pelvis area. I don't know what caused this, I wasn't doing anything inparticular that would cause any kind of injury 4 months ago. Any insight/help on this problem would be greatly appreciate it, thanks.
p.s. I've also gone and done an ultrasound on my testicles and there was nothing found.