Did icloud backup my photos and videos? I bought 20GB

hi so i just bought the 20GB icloud storage yesterday and let it backup for like 15 hours and i have 1,499 photos and 95 videos and im wondering that since i backed up everything while having 20GB, did it backup all of my photos and videos? because when i see my photo stream, it only has 923 photos

please help

(this is an ipod 5 running ios 7)