Pelvic pain and discharge. Suggestions.

I am unmarried and virgin.I am having right side pelvic pain which radiates to lower back and leg. It's been going on since three months. Scans like USG and mri didn't reveal anything abnormal. Just some thickness in endometrium, which as per my gynaecologist is due to menstrual cycle. Along with this I have issue of blood stained discharge in between periods, especially more after 2-3 days of periods but persistent later too with reduced quantity. Taken various types of antibiotics, 2 cycles of ovral g. After withdrawal bleeding from second pack of ovral g, I observed persistent blood tinged discharge. My gynaecologist gave primolut n and cifran. Today is third day I am taking these medicines, but still observing little bit of blood in discharge. I also get sudden pelvic pain,lower back and leg in between. I follow up with my gynaecologist. But I am afraid. I feel like it's something serious. I am really scared. Need advice and suggestions.