Burning sensation and pain in left abdominal area, accompanied by nausea and pressure in bottom area?

GERD. This can be gastritis, gerd, constipation, colitis, diverticulitis or ibd or many other GI issues i recommend seeing your pcp or GI doctor to begin work up and get you proper medications.
Colon Infection. This sounds like colitis or diverticulitis. It usually requires an examination and visit with the family physician.