Stress at work

Me

So I’m 22 weeks and everything for the most part have been going pretty good. Lately I’ve noticed I’ve been getting a little bit overwhelmed especially at work. We have been so short staff and a lot has been coming up I try not to over work myself but sometimes it’s hard and I really have a hard time knowing my limits. I don’t want to seem lazy or expecting special treatment just because I’m pregnant and i hate letting my co works down but at the same time I want to make sure my baby is ok! Sometimes I do to much and then feel my stomach start cramping and I have to slow my roll and that does scare me. How do I talk to my employer with out seeming like I’m just overreacting??

(Sorry a lot of info and a lot of questions lol)