They probably sillouetted you. Its ok to have the windows behind you cracked open so you can see if anythings behind you but you dont want them open all the way so the turkeys can see through. Also, how far was your decoy from you? You may consider moving it in closer to you so then when they hang up it will only be 30 yards. Were you doing any calling while they were close? If so they might have suspected somthing was up. Trust me when I say that turkeys do NOT care if your blind is in the open. I was set up in the middle of a field today in my monsterous blind and we had a hen come right up to us. I have had them 5 feet from my blind. Make sure the window flaps are secured so they dont make big movements. One of the flaps on my blind came undone right when that hen showed up and she took off when it flapped. Hope this helps. Good Luck next time!