The best way of dealing with the issue is to stay in your room and see if the noise repeats or gets worse. If so, bunker down and call 911.
However, none of us (including myself) take this advice so all I can suggest is making sure you have sufficient light to see into the deep recesses, go real slow, and have your wife beside you ready and capable of backing you up. No "gentler sex" thing when there is bumping to be dealt with.
