creeps at the gym🙃

I go to the gym almost everyday without an issue but today was a bit different. I use the squat rack a lot, but today while I was using it, these two men, who were WAY older than me, stood right behind me the entire time. They were clearly staring at me (the walls are all mirrors so I could see them) and didnt care that I noticed. They made comments to each other, and if I stopped squatting (i take breaks inbetween) they would pretend to not be paying attention, but once I started up again they came back. I ended up just leaving. This was just all really creepy to me, im 17 and dont appreciate men in their 40s staring at my ass. Has this ever happened to anyone else?