Contractions or?

Ni

So everytime I'm sitting down and then get up to pee my stomach gets very hard and tight and I feel like I can barely walk. No pain or anything tho. Is that just from having to pee or could it possibly be BH contractions (cause I've never heard anyone mention this when having to pee)

My due date was yesterday and as far as I know I've yet to feel any practice contractions