How do i know if there is something wrong with my ascending colon?

I think i may have overdosed on tylenol a few weeks ago. I took a lot, but wasnt paying attention so to how much so im not sure how much it was. I threw up a few hours later. My stomach really hurt, especially the left side. Anyways, i think im still having some problems, but it feels better. I just feel really gy a lot of the time though, and my stomach hurts more or less depending on what i eat. Ive been eating healthy mostly now though. But, the left side of my stomach area feels really sore sometimes. I checked a body diagram and found that the parts that hurt are located around the liver and ascending colon area. But im really not sure if the pain is inside my body or if maybe just some muscle or something is sore. I plan on going to the doctor, but im just concerned on whether or not it would be something serious or not??