Does your baby still give hunger cues?

This might sound a little dumb, but bear with me. When our son (5 months on the 22nd) was little, he'd do the rooting and the lip smacking and puckering and it would be clear that he was hungry (not to mention the eventual crying if we missed those things). But he hasn't done any of this for a while and we've just sort of settled into a routine rather than feeding on demand. Is that the same for you ladies?

We do sleep-eat-play with wake times of about 2-2.5h. He takes 3-4 short naps usually of about 40-60 mins and I feed him about 10-30 mins after waking up. I feed him when he wakes in the night, too, as he can no longer be settled by anything else. This is 2-4 times a night.

Basically my question is: is it possible I'm underfeeding him? He's been in the 60th-70th percentile for weight and he's a happy, smiley baby (of course he fusses and cries when he's tired or bored). I end up feeding him at breakfast, bedtime, and after each nap so 6 feeds on average during the day and then the short night feeds usually from just one side.

Any thoughts? Thanks ladies!