My one month old and I bumped heads..ouch?

He has reflux, so often, he arches his back and then his head whips forward, because he's too young to hold it upright...I always catch it, but one time he rammed his head straight into my jaw...it hurt me, so I can imagine it hurt him too...I was holding him with one hand and supporting his head from the back, but he just through it forward. He cried for a second then calmed down immediately, and started feeding as it was his time to eat. He ate well, then fell asleep and he seems ok, as he wakes up to eat every couple of hours and he's got some alert time, but he seems to be sleeping more than he usually does... is this just a growth spurt coincidence, or do you think he's sleeping a lot because he hit his head? He's smiling and cooing as usual, just a lot less awake time. This happened yesterday in the morning.