Ran out of CO2 when purging keg!

So I just kegged a wheat IPA I've had sitting in primary for 4 weeks. I took it to my kegerator to purge the headspace and realized my CO2 tank is completely empty! It's late Saturday afternoon so I probably can't get a CO2 refill now until Monday. Is my beer going to be ruined now sitting in a keg with oxygen?
Can't believe this!

This is quick and dirty, but, if I were in your place, I'd sanitize the outside of a poly bag(big enuf to fill headspace), make damn sure it doesn't leak, stick it in the keg, blow it full of air(breath), thru a cotton filter won't hurt, keeping the open end closed, and seal any spaces(I had success with a clean bag over the outside of keg also, but ALL must be sanitized). This may keep most of the oxygen off your beer. Good luck.

I would just leave it and not rock it around at all until it is purged. Treat it like a secondary until you get some gas

+1 to RDWHAHB

Transferring the beer caused some CO2 to come out of solution, and a little bit of oxygen for a couple of days isn't a big deal.

Go get a paintball CO2 tank from Walmart. I keep one (along with an adapter to connect it to my regulator) in case of times like this.

Even without the adapter you could just blanket the beer with CO2 and close until you can refill your bottle.

Thanks for the responses. I'm planning on just keeping the keg undisturbed and picking a refill up Monday morning. Kind of unfortunate but im hoping the beer wont be too affected by a few days with some o2.

Just thinking out loud here, but is there enough yeast left in the beer that you could slightly warm it up and toss a little priming sugar and let it self pressurize?

Does it really matter at all? Does everyone purge their bottles when they bottle? I don't really see how it's any different.

Gab, good point. I've never thought about that. I'm hoping, as others have suggested, there's still enough yeast in the beer to make a bit of CO2 while in the keg. Especially after being agitated from the siphoning.