If you're a primal eater and are fat-adapted, then too much sugar/starch can give you diarrhea and too much fiber can make you constipated. Perhaps you are sensitive to some kind of additive in the meat you have been eating? I've never heard of someone being allergic to organic beef for example. Or it's psychological aversion - did you used to be vegetarian/vegan?
I've heard of some people eating a SAD diet who can't handle a lot of fat at once, maybe it just takes time for your stomach to adjust the amount of bile needed to digest it.
I'm doing the GAPS diet which is similar to primal but starts off with a stage of very low carb and mainly meat and broth. Believe me, cooked meat is the easiest thing to digest. I wouldn't be eating so much of it if it weren't!
Start weight: 238 lbs (March 2012)
Current weight: 205 lbs (July 2012)
Loss so far: 33 lbs!!!
WOE: Primal + IF
Movements: Hiking, sprinting.
Goal: to see my abs some time in 2013!