I'd never fire a round into the ceiling. With my luck, it would either kill a person upstairs or go through the roof and kill someone on the ground a mile away.
Take your time.
The intruder's down and out.
Go to your tool box.
Get your magnetic stud finder.
Locate a beam, an upstairs wall or at least a 2X4 and place your shot well.
Then please, put the stud finder back in your tool box and then call the police.
Remember, 'haste makes waste'.
Gentlemen, I believe we have a new number one. ;^)