I think too much fat gives me stomach aches
Before going primal/paleo I used to get stomach aches quite often (like every couple weeks) and couldn't figure out what it was cause I was eating everything. Since starting this new lifestyle I didn't get a stomach issue for over 6 months. There's been a couple times recently when I have and I'm pretty sure it has to do something with too much fat or oil. One time was when I put butter on all 3 of my meals and also had 8 slices of bacon. The other time was when I had onion rings and a curry dish for lunch and a wendy's burger in the evening. I realize that was major sinning but I was out with family the whole day.
It may not be the amount of fat, but where it's coming from. Butter, bacon (processed meat), and fast food (cooked in vegetable oils and most likely with added wheat) can all trigger problems for some people, but you'd really have to do an elimination diet to figure out what exactly is giving you stomach pain.
Yes, there was too much junk involved in that meal, not too much fat.