Motion tracking inversion

I’ve got an issue that has been tripping me up for the past few days, I’ve been tracking a short video clip (solve error of 0.684, 30+ tracking points, Blender 2.77) which seems to be working fine, but when I try and set the scene the floor seems to be incorrect - possibly inverted. I’ve set the floor according to my tracking points, as well as x/y, origin, etc., but nothing seems to be fixing the issue, the floor’s perspective is always upside down. I’ve tried inverting the camera manually, but I always end up throwing other things out of whack as well. Tried using other clips and I’m consistently getting the same problem.