is it possible to have a swollen belly with weight gain with

Is it possible to have a swollen belly with weight gain with an enlarged uterus? Also why would there be blood fluid in the uterus if you are in
menopause?

If your uterus is enlarges, it could be fibroids. Uterine fibroids are benign growths that occur in the uterine lining, or even uterine walls and they could grow to bi so big that a woman could look pregnant. If you are approaching menopause, you are suspected of developing fibroids but if you are already in menopause then it is highly unlikely you would have fibroids as they shrink in menopause.

Have you been found to have blood fluid in the uterus or you have experienced some kind of bleeding?

I don’t think that your symptoms are associated with weight gain if you have enlarged uterus as well as bleeding in the uterus. A gynecologist evaluation is needed to get the proper information.