Job makes me clock out to use the restroom?

I work at a call center in Oregon if that makes a difference, and we have to clock out to use the restroom. We have to select that were “on break” just to use the bathroom. We’re not paid for breaks or lunches btw. And they told us if we use the restroom too much, it will cut into our break time. This makes me nervous because I have very heavy periods. I haven’t started my period yet while working this job (only started a few days ago) but I have to change my tampon about every hour to prevent leaking. Can I get fired for this? And is what they’re making us do even legal?