Any guesses?

I am a 34-year-old female and have been having right-sided abdominal pain on and off for about a year.  My bowels are sometimes quite constipated and sometimes have diarrhea.  My doctor ordered a ct abdominal and pelvic last week with both oral and IV contrast.  I was told I have an inflamed area inside the colon, that there is a, "round air-filled focal area.  I was told I needed a colonoscopy and the GI center (based off the referral) is having me do in two visits what most people do in three to speed things up.  The doctor's office said "it" is in my sigmoid above the pelvis.  Has anyone any idea what this supposedly air-filled thing may be?  Is it part of the inflamed area?  What kind of a diagnosis does this point toward?  Btw my cousin has crohns pretty bad.  Any ideas would be appreciated!

[Caryopteris]

Most likely it is diverticulosis since you have constipation.