what should I do?

Karissa • Mommy of a 9 year old little man (6/9/13) , 4 year old little man (9/13/17) and a 5 months baby boy (6/13/22)💙💙 RIP My Angel 9/23/2020👼.
So I have been having contractions while at work, they aren't like horribly pain full but deff bother me. I'm 28 almost 29 weeks and it only happens when I'm at work. I do stand all day while at work. Should I get this checked or even go to er to be safe? It's been happening for the last three days now. Opinions please!