Hard lump on back side of testicle, is it a calcium deposit or cancer?

ok so about a year ago I found a small hard spot on my left testicle, I went and got a ultrasound and they said it was a calcium deposit. Now I just noticed today that I have another hard bump about the size of a bb on my right testicle on the backside. Great!LOL. So could it be another calcium deposit or cancer? Its attached to the testicle just like the one a year ago was, does anyone else ever get these calcium deposits on your testicles? Thanks