Cereal Painful?

Wow - I haven't had cereal since i was banded cuz I usually go crazy on it and can eat a whole box - however, I tried Dr. Sears High protein low carb cereal mixed with a lowfat yogurt yesterday and it went down ok (i ate really slow and 'chewed it" and while I felt it going down - it felt kinda hard - i ate about 1/2 cup. I have to say i was 'sore' yesterday and ended up on liquids through dinner = not a pb but sore. I think it was too crunchy/hard but I've never experienced it before. needless to say i will be more careful in the future - maybe try softened in milk or not at all. Just curious if anyone else has had this with cereal or other foods.