I Have Been Sick Since Mid-November With What Started As

I have been sick since mid-November with what started as a gnawing heartburn feeling that caused me to be very nauseous in the mornings. After a few weeks of throwing up throughout the day, I went to the doctor at Immediate Care. The Doc did not conduct any tests, really, just told me he thought it was gastritis and prescribed me some OTC anti-acid meds and anti-nausea meds. Taking these did not really help, so I made drastic changes to my diet to see if that helped (i.e. I stopped drinking coffee and alcohol completely). I am still feeling the upper abdomen gnawing-feeling and nausea. I have had irregular menstrual bleeding for the last month to two months, and have been getting progressively more bloated in my lower abdominal area. I experience sharp shooting pains on either side of my lower abdomen (feels like the ovaries) if I stand up too fast. I have been getting dizzy spells and headaches too. Please help.