well if its the duct, it could be just swolen from an infection. thats easier to tell though because it would be softer but sensitive to pressure, not just touch. and it would be swolen on one of the bump looking thinngs next to the nipple because those are the ducts. gyno occurs on the actual gland which is just a bit deeper
this happened to me a little over a week ago. i went to the dr thinking it was gyno, and he said its a minor infection caused by sleeping in a shirt that rubs from tossing and turning in bed. it also happens to runners that run with loose shirts
i think the difference in treatments are pretty obvious now lol