Q: Could not load video

Hello _mary_12,

I would try downloading the movie in iTunes to get your purchase first and see if it will play there. If it does, then delete the movie from your iPhone and download it again. If you are unable to download it again, then sync the movie with iTunes. 

Download past purchases

http://support.apple.com/en-us/ht2519

How to delete content you've downloaded from the iTunes Store, App Store, iBooks Store, or Mac App Store

http://support.apple.com/en-us/HT5772

Regards,

-Norm G.