Waking every 2 hours

Kris

My little guy is 3.5 months and for a few weeks he has been giving us 4.5-6 hour stretches during the night, but these last few nights have been awful, waking up every 1.5-2 hours in the dot! Last night was the worst of them all he was waking every hour and a half crying and just wanted to be held to go back to sleep. Anyone else experience this? Is this normal at this age.