Growth spurt?

We think Junior may be going through another growth spurt the past couple of days.  All of a sudden he seems to look HUGE overnight.  His belly is quite protuberant.  He's eating more frequently, and he's more fussy than normal.  Even though it was a gorgeous sunny 70 degree day, he didn't want to look around at all during the stroller ride.  He wouldn't stop fussing until I covered him completely with the canopy for the perfect sleeping environment.