Gas,?

Anna • 💙mama to noah💙 03/08/19

I can't tell if my 12 day old has gas or not. Last night he def did as he was crying so much and finally stopped and slept once he let out a big fart lol. This morning hes been good but super fussy after our 2hr nap today at 6pm. He will cry and lift his legs up to his chest, but stops and falls asleep once I feed him and hold him. Does them being fussy and bringing their legs up to their chest always have to mean gas ??