I'm a 33 year old female, new Mom to a 10 month old and for the past few months I've been experiencing stools that are flat on one side, they seem to be normal size but flat on one side (it is as if they have been sliced). they are always this way, they are never round anymore. 2 1/2 years ago i had a barium enema when I was experiencing IBS symptoms and it came back clear. I am terrified to see the doctor about this. Has anyone ever experienced such a thing?

Yes and it was a symptom of my rectal cancer
BUT
it simply means that there could be a partial blockage there which, given your recent childbirth, could also be due to hemmerhoids so do not panic. Make an appt with a doctor and in the meantime you may want to try Prep H suppositories to see if it reduces any swelling inside.