issue with AMD Demon floor pan..please help newbie

I know it was already suggested but I never heard him say he did it. It looks like its sagging to me but a string stretched across would verify it its sagging or not.

i ran a straight edge across it and it seems fine to me, then again im not to sure what its suppose to look like. also i put the trans mount in and it fits, so i dont think it is sagging coz if it was i dont think the trans mount would fit