Still from this pic, looks like a screw short top left (just left of 4 pin power connector)
I would make sure that all the screws that can be used to fix your Motherboard to the chassis are used.
Enjoy your new build, practice makes perfect ......

Hey I know someone who has built loads of PCs over the years and he did just that a few months ago.
I was waiting for it. Wrong VGA....we've all been there at some point. Move along, nothing to see here.
Looking at the later pics, he still looks like he missing some risers and screws, as the mobo dont look secured or lined up well. Like mentioned, top right need a screw to hold it, but it is missing, so what has the mobo been aligned up on.