Is something wrong or am I overthinking things?

This is my third pregnancy. My first tried to come at 33 weeks but ended up being born at 41 weeks via emergency c-section (thanks breech birth!) and my second was a 1st trimester loss.

I’m currently 30+4 weeks now, and so far things have been going good. But the past couple days, my back has been killing, my stomach feels like it’s carrying a 5/10lb brick in it, and I’ve had a couple intense menstrual-like cramps that also come with nausea and hot flashes.

Should I be concerned?? Like, should I be calling my OB as we speak? Or is this kinda normal and I’m just overthinking?