Can a small ovarian cyst that hasnt ruptured cause discomfort, nausea, pelvic, and lower back discomfort, pain in upper legs, can't eat, freq. urination?

Yes: Sadly, an ovarian cyst can cause discomfort, nausea and pelvic pain. Pain in the upper legs and frequent urination with a small cyst is likely something else. You may have a bladder infection on top of having a cyst? If you've lost your appetite as well i would see a doctor for an evaluation as you wouldn't want to miss something. Best of luck!