Krouth, am I correct in the broker submitted your offer to the seller's NOT USING a P & S agreement?
Also, is the broker the seller's broker, or a buyer's (your) broker?
Either way, a professional, ethical, and responsible broker would have used a P & S, with included provisions, such as "subject to inspection, survey, obtaining insurance, etc, to extend the offer to the seller's, and would NOT have told you, the perspective buyer that the offer was accepted until he had the P & S (signed by the seller's) physically in his hand.
Any other behavior on the part of the broker is neither professional, ethical, or responsible.
If the broker is your broker, fire him and find another broker.
If the broker is the seller's broker, fire him and find another broker, or walk on the deal.
Best of luck!