Right there is where you made your mistake. Experienced bidders know that when they get a message like that from Priceline they are already very close. The thing to do is refuse and up your bid a dollar or 2, you will get it anyway. There are different strategies on how much more to bid after you get this message (I just continue on as if there was no message at all) but even the highest recommendation is to bid half of what Priceline is asking for.
You sound like you would have had a rotten time no matter what the price but at least you would have won it on your terms, not theirs.