My iMovie doesn't detect my video on camera roll? (ipad 2)

I have iMovie and for whatever reason, a video that I had recorded 3 hours prior to buying iMovie does not show up in my camera roll. This is the only video I have and I cannot replicate it, so I need this footage for my college project to edit.

Is it even possible to obtain footage from my camera roll to use for iMovie, or am I screwed? Or maybe there is a way to rerecord that footage?