I think you should have that uterine fibroid taken out of there forthwith. You have the fibroid, it's possible it's grown large enough to cause you discomfort, and I do not understand how come your gyn doc is letting this thing go. With your history and symptoms, the safe route is THE way to go, and they need to either do the ultrasound as the other poster suggested to see how that fibroid is doing and see if there are others, or better yet, I think a CAT scan is in order, it's a better diagnostic tool, and since you already have a fibroid, I think it's okay to go the step-up in type of test. Go to another doctor if you need to, even the county health clinic docs can order one for you, they can see you as a walk-in on the same day and order the scan, and then you wait a while to have it done.
See, if you didn't have the fibroid to begin with, I wouldn't worry. But since you've got that thing, not only could that fibroid be a problem, but also as the other poster said, could be you have yet another growth in your pelvis causing you problems. Your history of a fibroid, your symptoms of pain and the bathroom thing, all this points directly to a risk of either your existing growth getting too big or another one growing too big in your abdomen, too.
There is absolutely no reason on earth why you can't have a scan (other than insurance company cost-oriented non-reasoning), becuz when you look at the cost that physical damage an invasive fibroid can cause, it's cheaper in the long-run to be safe than sorry. I have read too many stories about the wait-and-see approach with gynecological tumors, that can turn out lousy for the patient. Sure, some growths don't cause problems. But when they DO cause problems, by golly, the doc has got to switch gears and prevent, prevent, prevent.
A very large fibroid can cause similar problems but you'd be having very heavy periods too. I would insist on a transvaginal ultrasound to look for an ovarian cyst. That is an easy one to rule out and the symptoms definitely match.