Sleeping alll day????

My 3 month old for the past week has been sleeping all day this week. He wakes up for feedings every 4 hours, still eats 24 oz a day, regular wet diapers. But he seriously only wakes up to eat. No temp. But he's extremely fussy while he's awake for his bottle then falls back asleep right after. Is this a growth spurt, I'm trying to incorporate tummy time during the day but if he wants to sleep all day that makes it hard. Anyone else in this boat? He sleeps all night too.