Most Helpful Girl
I think you should just wait until he responds... then apologize.
Probably say something like, "Sorry, I thought you were awake. I was just in the mood for seeing you during that time."
And quickly brush it off.
It's not a big deal.
Trust me, he won't care much.
It's not like you obsessively called him at 2am in the morning.
Then u'd really need to justify.