Cap popped off secondary, worry?

Hi all,

A quick "should I be worried or chill out" thread. I went down to throw a second round of coffee in a coffee stout I brewed last Sunday, and the red ipa I had in my secondary lost its cap. (in a 5 gallon water bottle same material as a better bottle, so basically a better bottle) the cap was a bung that didn't quite fit so I turned it upside down and plugged it.

Should I be worried that the beer was sitting out without any cover from the air? It was maybe 2-4 days that I checked on it so I have no idea how long it was. I sanitized a piece of tinfoil and placed that over top, and now have the bung on top of that.

Arghhhh.

Plenty have fermented open top with no problems. Something I might do just for fun with a small batch eventually. I wouldn't worry about it. It should be going in the bottles pretty soon right?

By "lost its cap", do you mean it fell on the floor? Or that the cap was sitting on top, but not a snug fit? Either cases I'm sure you'll be fine, but even if the cap sits over top of the hole I'm sure it would affect the beer at all.

Thanks guys, I'm hoping to bottle in 7 days. That would be 10 in primary (after stable hydgro) and 14 in secondary. The picture below shows, the bottle in the back is the one the cap "popped" off. The bottle in the front is how the bottle in the back was.