Might be from the stretching, I don’t know. However, I would be surprised due to the fact that during my stint with the Bib Hanger, I often hung with blood in the glans. No change in shape or deformation and that’s quite a bit more intense than manual stretching.
Is it possible that it was present all along and you just now started noticing it? Yes, it sounds like a dumb thing to ask, but sometimes the new found “penile awareness” that comes with PE is kinda tricky. I actually never realized that I had a light torque to my dick until I stated PE and was therefore inspecting and analyzing it alot more.
If it is a new thing, perhaps it’s a blister or irritation. Is it puffy? Does it look as if it is primarily a skin feature and not something deeper and more substantial? Could be local swelling, a callous type effect…elaborate, maybe someone will identify with it and give some advice.