If your just tired... you can have the strength to do it. Soon you cant work at all. I know its hard but you can do it.
Let them count your restroom breaks, as long as they dont write u up for peeing. And if they do it can turn into a lawsuit.
Talk to your doctor, have him/her write a letter you need to rest and can't over work, I had the same thing and I work in a medical field. They even counted the times I used the restroom which was horrible because I'm pregnant and baby kicks bladder which makes you pee a lot. Some people think being pregnant is super easy and that they are all the same