Female balloon Molly on bottom of tank

Hey guys, I have a 30g tank where a sorority of Bettas and 4 Female mollies hang out. The tank is cycled and has been rolling with the current batch of fish for close to a year. Recently, I noticed one of our female mollies hanging out at the bottom corners of the tank. She comes up to eat but that’s it. Her stomach is a little round, but that’s the case with most molly fish. What may this be? She could be pregnant, but if not that, then what? The water is flawless, and is tested every 3 days, with the last test being yesterday.

 

She has no outward symptoms as far as I can see.

 

Bump. Breathing is heavy.

 

Any help? Or advice?

 

Sorry no has replied yet.
How long has her stomach been like this? Maybe she is in labor? Her stomach looks pretty squared off which is a sign the are about to give birth.
She could just be bloated though. I have experienced this when my molly was bloated because I overfed her

 

Does anyone know how long Mollies are in labor for? I have a black Molly, just got her yesterday. I am about 95% sure she is pregnant.

About 10 minutes I went to check the fish tanks, and she is now staying behind the sponge filter, near the heater, not really moving. She backs up a bit, goes up and down a little, but that's it. I can't see her too well, to check her breathing or anything.

Any help would be appreciated. I also noticed this white area, around her anus, is bigger today, the it was yesterday. Last picture is