Hi, it could be either way. My mollies look juuust like that even up to 24 hours after eating sometimes but then they poop it out and 'lose weight' ha. Your molly doesn't really look pregnant to me tho she's probably just full. When mine are pregnant they're usually a lot bigger and it's sides get fat as well. When mine are gonna burst so to speak they start to struggle with swimming a bit and for a while before they're gonna give birth they'll kinda just look straight up and sway a little side to side in place. If she's consistently fat and even keep growing then congrats!