Anyone else feeling this around 31 weeks?

I have burning pains that come and go they take my breath away. It radiates throughout my whole abdomen and around to my back with a tight squeeze(dr says contractions). If I dont sit down usually because im outside with the kids, I get lots of lower stomach pressure inbetween the burning pains. Then when I am able to come in I have mucus plug in my underwear.

Should I be concerned? It get the burning pains every day and usually get them to calm down right away if I can and if I can't I get mucus plug down there.