Pto 4 Potty Breaks??

I work a call center job rn and I had been just going to break code to go pee like I was told to. Just a quick step away to pee, easily less than 5 minutes a time. But I was told I was out of my break allowance ….I asked if I should shave time off my fifteens or skip a 15 so I could use the restroom when I needed because I gotta pee. Well they told me I can’t do that, that I needed to use my full fifteens at the time I’m told to. So I asked what I should do if I need to pee when it’s not a scheduled break… I was told I’d need to clock out and go through a calling out and log for pto if I was going to be over my break allotment or go get a dr note. Im over my break 2-4 days a week but never more than 5-7 minutes. They said I’d need a note from a doctor for a workplace accommodation or I gotta use my pto. I’m not big on making a fuss about stuff but that just feels illegal and if it’s not it probly should. I have it in a writing from management to use pto. I’m dehydrating myself trying to not have to go. I dunno what to do... Obviously I can get a note, but I don’t think I’d need it just to use the bathroom. Ain’t got a union or anything like that.