Uper stomach preassre

Alyss
20 weeks and 5 days and for the past 2 days iv felt like a pushing feeling like my belly is about to pop im thinking baby is just im a bad positioning... I have a ultrasouns today thankfult but just curious if anyone else has gor this in upper belly cauae i dont remember this when. I had my son almost 5 years ago.. Rhank tou