What Could A Small,soft Glandular Like Lump On Left Testicles Be ?

I noticed a small, soft, glandular-like lump, about the size of a pinky fingernail on the top of my left testicle, but I feel it only when I am urinating throught the zipper hole in my pants. Sometimes I can find it, and sometimes I can't locate it on top of the left testicle at all. I have done extensive comparisons side by side and both testicles, after I examine them, produce no findings. I have no discomfort in my abdomen, legs, back, etc. I have no discomfort or swelling in either testicle. Urination is normal and unimpeded. When I examine each testicle, the testis are smooth, egg-shaped, and no lumps are detectable. I'm not sure if it's cystic in nature since, when I dig deep enough, I find 1 gland-type nodule that is in the same place near both testicles and are painless. Am I just worrying myself to death ? I am in the medical field, so I could be " over-thinking " this.