Whiff of burning smell??

Hi everyone, I just woke up from a dead sleep to a strong burning smell, and then it was gone in an instant. I’m not sure how to best describe it other than it did not smell like a dead animal or rotten eggs. I checked the entire house and no appliance other than the fridge is running. I went to each room and none of them had a distinct smell from any other. We’ve had the heat mostly running for the past few weeks since it’s been cold, so I’m not sure if that could have anything to do with it. Am I going crazy?? What could this be?? I feel like I can maybe smell the smallest hint of it but I’m not sure if that’s my anxiety making me smell things or not.

Edit: when I first made this post, I hadn’t woken up my husband yet to see if he could smell it. When I did wake him up, he could smell something lingering, but it wasn’t as strong as the smell that woke me up initially. So not a dream!