Baby got gas

Isaac has been fussy the last two days. I will not use the "C" word. He is just gassy.
Now I have to start thinking about whether it's something in my diet (milk? nitrites? tomatoes?) and decide if I should change my diet. Evan was allergic to cow's milk protein, which he got through my breast milk, and his colic mostly resolved itself when I cut out dairy.
He's been fussy off and on for a couple hours. Usually he just cries for 5-10 mins at a time, and feels better when we put him on his tummy and pat his back. So he's not inconsolable. But I still feel bad for him.