REO seller trying to back out of contract North Carolina?

I am currently under contract to purchase a REO owned by Fannie Mae. I am supposed to close in two days. Last week my agent had some contractors look at the house to give estimates. The contract started to do some work on the house without verbal or written authorization from either me nor my agent. The sellers agent contacted us immediately and the contractors were told to leave. My agent got into an argument with the sellers agent and it ended with the sellers agent saying we may cancel the contract and hanging up on my agent. Since then the broker in charge for my agent has been trying to get up with the sellers broker in charge. No response last Thursday. Last friday they made contact and said they are waiting to hear back from Fannie Mae's et manager. Monday no response. Tuesday (today) still no word as of 10 a.m. I am supposed to close in 48 hours. Have put off the title search till i hear back. I already have almost 1,500 invested in commitment fees, home and pest inspections, appraisal, hvac inspection and pump inspection. Can the seller cancel this contract in North Carolina? Will I receive all my earnest money back ($5,000) AND the 1,500 invested. I heard of something called "specific performance" which could force the seller to sell? What do you think my options are? Has anybody dealt with REO's and Fannie Mae? I'm all set to close and both invested monetarily and with emotion now. Any advice would be appreciated. Thank you.