i don't consider the price going up $25 in a short time to be a bubble. if it went up to $800-$900 right now after sitting under $400 just a few hours back, then it would be completely different. right now the price is recovering to its normal price level. it was about to happen and many people were expecting it to happen within this month, and it did.
It happened very sudden though
The price flash crashed 60 dollars last Friday. This was a recovery/correction.
A bubble is what happened the first week of november...approximately 250 spiking to 500.