I'm sure this is completely normal but Google is useless when it comes to health. I can feel this tube on the bottom of my testicle which is on both so I'm pretty sure it's just a normal tube but I've noticed when I masturbate the tube on my right testicle shows up on the right side of it and it kind of bulges out and I can feel it, it's not hard or anything and I think something like this happens on the left testicle on the left side as well but I've payed more attention to the right. The tube will go back to smooth after a little bit. And there is no pain or discomfort but it does have me a little concerned. I am 16 and not really active right now from a knee surgery I'm recovering from but when I go back to work I will have between 10-20 thousand steps a day. My mom makes only healthy organic meals but I'll go out and buy fast food and drinks and food from the store but I don't think it's that bad with the balance. I'm also nervous to bring it up to my parents because it seems like an awkward conversation. Does anybody know? I tried to give as much information as I can think of. If more is need please let me know.