Reddit, what was your biggest "Uh-oh" moment?

The evening before flying to another country for my wedding, I discovered that my passport was nowhere to be found. Families and friends had flown over, some from different continents. Wife to be was already there.

I regularly took it out on nights out as ID, and had lost a previous passport in this way and not noticed for over a week.

Cue four hours of ripping my flat apart try to find it. Because of local laws, I knew that if it had been dropped when out and handed into the police, they would cancel it without consultation.

In tears, with my whole place upturned, I prepared to Skype her family to break the news.

And then found it. Lodged in the sleeve of a hoody that was among clothes I had set aside to give to charity.

Didn't tell anybody.

I was shining a laser light onto the flight deck on people walking around and about 45 seconds later I hear a knock on my office door. Uh oh.

Looking up. See light through the window, it's not the streetlights again. For the record I was 8.

Riding downhill mountainbike down Alpe D'huez, France. I'm on the border between being very brave and very dumb so I decide to smash down a track that is above my skill level.

Everything goes great and I'm surprised about how good I'm doing and a few seconds later I smash through a sharp U turn, full speed. In my flight I see that I'm heading straight into that pit of rocks 3-4 metres below me. That was my biggest "Uh-oh" moment.

When I punched my brother in the face one day while he was picking on me. Also when I told my dad it was stupid that he didn't let me do something, can't remember what it was though. "Are you callin me stupid?!" "No I'm saying what you said is stupid." That pissed him off.

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