Burping??

Not sure if I’m pregnant or not, we haven’t been trying but with sex comes a chance of pregnancy. We only use condoms. But anyways the last 3 or so days I cannot stop burping, my stomach is so grumbly and ive also had slight heartburn but only noticed that today. Not sure when I’m supposed to get my period, I was taken off my BC about a month ago and had really irregular periods the entire time. Did anyone else have this happen before they found out they were pregnant?