My nips are puffy - but it sure does play mind games with you.
Ever since puberty, they've been puffy. I do "feel" something behind the left nipple, and not the right one.
I'm currently taking M1T, and I find myself feeling my nipple area everyday now (and not just cause I like rubbing my nipples - which is a different story
I don't think the M1T made them any puffier - BUT - because of my bodysize/definition, I am concerned with what other people would think. (My nips are naturally puffy, but others may think it's from steriods or something due to my physical size).
Who knows - with enough big guys getting puffier nipples - "average" people may just start thinking it's a normal thing...
Heck, I wouldn't doubt that someday, people will start getting surgery to make their nipples bigger. You never know where fashion is going to go next. LoL