That's not good, I know when I was in school quite a few guys used to get erections in the showers, one guy used to openly play with his all the time, a few times when there was a few of us who were friends in there we would join in
I’ve always stayed flaccid, but couldn’t help checking out the other cocks. Same at public urinals. Probably the high point was taking a piss next to a coworker who is a total asshole. It was great peaking over and seeing his super skinny dick!
In the gym shower, just twice. Didn't care. I get them in showers with friends and family ever so rarely anymore at my age (42.) Like once every five years it'll happen. But only with people I feel comfortable with it happening in front of. My only weakness to this day for public erections are beach changing huts. I mean every single time. In fact, I'm a total nudist, never embarassed about my body or anyone seeing my penis in any state. But to this day, that's the only circumstance where getting an erection in front of people embarrasses me because they're like solid hard and pointing up. And I worry the other people think it's a reaction to them when it's really more about me getting it into my head that I don't want to get one. Which basically makes it happen. When I was a teen my dad would very sweetly stand in front of me to give me some coverage.