What Causes Severe Vaginal Bleeding?

I am a 27 year old female. Symptoms: severe vaginal bleeding 2 months plus...pelvic and abd pain...had an ultrasound done...findings : Mildly enlarged anteverted uterus endometrial echo 21mm...uterine fibroids largest measuring 3.6 cm, normal ovaries. I went to OB and he did pap smear and put me on Provera. Should I have alternative testing done?