IBS or something else? TMI

[unhingedtoday]

I suffer from really bad IBS with diarrhoea. I have given up many trigger foods over the years and so have a pretty safe diet.
We went to some friends for tea on Saturday and had roast chicken (yum) with all the trimmings.
Now, I always get a bit of a bad tummy the day after eating roast chicken, my poo smells a certain way every time and I get some cramps etc, nothing too bad.
Since Saturday night I have felt rotten, my poo has been horrendous my stomach has felt sore and raw, a bit like it was when I had gastritis. I also have terrible heart burn. The chicken was cooked fine and really tasty!
I have also been diagnosed today with a double ear and sinus infection so feeling pretty shitty.
What I want to know is if these just sound like IBS symptoms or whether it sounds like a bug?