I had a molly a while back that looked just like yours. The belly was a little bit stretch out, but I never saw the dark spot that's supposed to be the fry. A few days later I had a bunch of fry in the tank. I would pay attention to her behavior. If shes moving a little slower, staying away from the other tank mates, and eating more shes probably about to be a mom.
Defo not over feeding they all get fed once a day, and none of the others are like this. The fin still looks fan like the other females I have think it was a bad angle for the picture. But it is quiet transparent