AITAH- refused to give up “my” treadmill

So, I’m currently on a cruise. Every morning I get up early and go to the gym where I jog 4ish miles before breakfast.
To be transparent, there is a posted sign saying that to be fair to all guests, the treadmills can be used for 30 minutes at a time. They actually turn off at 35 minutes to give you time to cool down.
Anyway, today like every other day, I went up to the gym. I chose a treadmill knowing that that specific one doesn’t shut off at 35 minutes. (If I can’t get one of those, I do 35 minutes and then have to restart the treadmill to get my time). I have never been in the gym when it was full. If there were no available treadmills, I’d follow the 35 minute rule and get in line again to be fair. Anyway, because the treadmill I got on today doesn’t shut off, you could see how long I was on the machine. So, I’m minding my own business doing my thing. There are a dozen empty machines around me. An older lady comes up to tell me that my time is up. I pretend I don’t hear her. She again tells me that I’ve gone over the 30 minutes. I am honestly confused why she’s even talking to me. Again, the machines on both sides of me are empty. She keeps at it that I’m breaking the rules and she specifically wants to use the treadmill I’m on. I refuse and tell her to pick any of the several unused machines. She goes to get the gym guy who also seems confused as to why this woman has an issue. He ends up telling her to pick any different empty machines. She complains and finally goes away. I finish my work out, clean my machine and turn in my towel. As I’m leaving, the gym guy basically says to keep peace, I should have given up the treadmill. I was like whatever dude, she was just being a nosy troll.. anyway, I refused to give up the treadmill, AITA?