Bastids!!!

Our realtor just called. Someone else put an offer in on said 2-flat and the owners accepted! Grrr!!! What I don't understand - our realtor said she never got the seller's realtor to call her back! She talked to his assistant multiple times, but never the realtor himself. So...as someone selling a house, if you knew you had a second buyer VERY interested, going back for another look today, wouldn't it be in the best interest of your seller to wait for another offer to come in?! I mean, I'm not saying we were definitely putting in the offer, but why wouldn't you wait? OR at least call the realtor back. I almost feel like something shady has gone on. I'm totally pissed.