Feeling "inflamed"

Hello, everyone.  I am about 10 1/2 months out (RNY) and am having some "issues" today. I'm not sure if it is related to what I ate or not, since I have never had this kind of pain and duration of pain since my surgery.  My stomach felt fine this morning before I took my vitamins and ate some macaroni and cheese.  I have eaten mac and cheese before and do not remember any problems, although it is not a common food in my diet.  A little while after eating I began to feel uncomfortable in what I describe as my intestinal area.  The pain has increased throughout the day.  Once, I laid on my right side and it seemed to ease up.  However, a little while later, it returned.  It seems to mostly be on the left and in the center of my stomach area, both high and low.  It feels like I am perhaps inflamed somehow on the inside.  Is this possible?  What can I do?

Do you still have a gall bladder?  Mine felt like I had a brick under my ribs and my back hurt.

No, my gallbladder was taken out a few years before my RNY surgery.

maybe an ulcer?

Just an update.  I went to a much simpler diet (mostly clear liquid) for a few days and realized that the pain wa****ting me mostly whenever I took my calcium citrate pills.  It felt like someone punched me in my stomach when I took them at one point, and I realized that the pills were a common denominator in the times I hurt the most.  I've stopped taking them and ordered some calcium citrate chews from Bariatric Advantage.  Hopefully they will be here soon.  Today is my first pain free day this week.