Cramps and low pelvic pain?

Ti

This is my first pregnancy (18+2) so of course I'm clueless. I've been having cramps here and there for a few days but chalked it up to normal baby pains. Today I woke up with a lot of pressure and pain really low in my pelvis and the cramps are still coming and going. Is this normal? I can't get a hold of my doctor until tomorrow, should I just go to the ER?