Was dealing with COVID back in April and felt better by May. Havent had any issues till now, but for the past 45 days, my stomach's been feeling really tight like Im constipated. Not much gas is coming out, even with rantac 150mg. There's also this chest tightness and occasional pain, especially on the left side and in the middle bone of my chest. Is it just gas, or could it be something else? I'm kinda worried.