Or is it the food I had in the morning or the day before that is being pushed down by what I'm currently eating and THAT'S what's causing the sudden urgency?
Gonk said what I was going to
A very inflamed colon gets stimulated by almost anything, even water. Not sure if I'd call that IBS. Later on when only certain foods/drinks cause it or only at certain times (such as active colon in the morning) then it might be IBS, or not.
The long lead-time between eating/drinking and when it gets to the colon made determining what foods/drinks caused me problems so very (very) difficult. Sometimes it is the food and sometimes it's your wounded gut speaking.
I suggest cutting out nuts and any type of fiber to let your gut have time to heal. Doctors call it "low residue", I call it low fiber plus adding no-gluten no-grains no-dairy. Easy? No, but I wanted to avoid surgery so was willing to do it.
Eat chicken, chicken broth, veggie juices and use olive oil and coconut oil as much as possible for good calories (by the spoonful). Not all of SCD worked for me (almond flour notable) but some of it did.
Current diet=modified Paleo (sm amts of swiss cheese and some fruit OK)
In remission April 2010 after 10 years of UC with no remission ever
gluten-free (bleeding stopped) and dairy-free (less gas) started remission path+food diary
current meds=(9)Balsalazide+(2)Citrucel,(1) VSL#3 nightly
Rx meds have never worked for me except for mesalamine enema