Hi Home Selling, sorry to hear about your predicament.
As with any contract, you should turn to the terms and conditions. I'm not familiar with the FL sales contract and if there were terms and conditions noting that the sale is short... Check with your agent or, if you don't have one, give the contract to a lawyer for review.
In WA, we use a contract that defines what happens when you buy a short sale. There are time periods set up and the contract is contingent upon the bank appproval and certain timelines - including the close date - don't begin until bank approval.
I hope that helps... good luck!