In those "I can’t believe that just happened!" moments…

I giggle. Hysterically.
Take the time our family traveled through Arizona several years ago. Hubby stopped the car to snap a photo of our younger son standing next to a giant Saguaro Cactus. I stayed in the car, watching. Back then cellphones weren’t camera capable, and Hubby had his eye pressed against the camera. Trying to get the whole cactus in the shot, he backed up, backed up some more, and WHAM! Stumbled backward into a ditch. 
What am I doing? Giggling. Hysterically.
And then there’s the time hubby was doing some work in our attic. He was moving around up there, not exactly light on his feet, and WHAM! Slammed through the attic floor. Somehow, he managed to straddle a rafter, and I looked up to see his long legs dangling through the ceiling.
What am I doing? Giggling. Hysterically.
This weekend our two-year-old grandson huddled near hubby’s vacant recliner. I pulled the lever to lift the footrest (for whatever reason, I can’t remember now). I stuck my hand in front of it to avoid hitting him. Did that help? No. WHAM! The footrest lifted up with such force, it whacked Mason in the side and catapulted him a couple feet in the air.
What am I doing? Giggling. Hysterically. Thankfully, he thought it was a game or a weird kind of ride, but how sad is that?
What about you? 
How do you react in those “I can’t believe that just happened!” moments?