I've shot a lot of 16mm, but this is my first time shooting stills on 35mm. I have no clue what went wrong, out of 24 exposures only 15 came out, the others weren't exposed. Guy at CVS said that I 'forgot' to take those ones. It wasn't the last nine that came out, they were random frames that weren't exposed, and I know I took all of them, so I'm not sure what happened there. Also, there are various things wrong with a lot of the ones that did come out.

Not sure why the bottom half of that is black.
If anyone has any ideas why 9 of the pictures didn't come out at all and why the picture above is like that, I would really appreciate hearing them before getting the next roll.