Belly very hard often 😳 worry

I'm 33 weeks and my belly is for the 2 last week getting hard very often, specialy for the 3 last days. It can last 1hour in contraction, it's not painful it's just very uncomfortable and I have to lay down and sleep to feel better. A bath works too. Should I be worry and go to the hospital to check or is it normal? It happened like 4 times a day... For 1 hour each sometime.