It was a good offer.
By the way, as a domain reseller, I might be interested at around $10,000 range for the domain if in case you like to sell it in near future.
This confirms that the original poster's "loss" in "blowing" the deal is only in the $8K to $15K range.
Also since there are few if any repeat "retail" customers, brokers have a tendency to make repeated "final offers," so don't count yourself out yet. It would be laughable how many times people say, "my last offer is $25,000" and then come back with one or two more offers (if you are in the ballpark, not in fanasy land). Since they will never do business with you again, there is no reputation effect to being full of it, so talk is cheap.