I Have Been Experiencing Nausea And Burning In My Upper

I have been experiencing nausea and burning in my upper abdomin, a headache and the urge to make a bowel movement but often the inability. When I can go, it's a yellowish green. This has been going on for over a week. I am taking antacids and driving plenty of water. Is this a virus or something that will likely resolve itself or should I find a doctor?