all my pictures from camera roll disappeared!!

i had thousands of pictures on my camera roll and they all of a sudden disappeared!! according to my storage there's still pictures on my phone but my camera roll is empty. i searched for a solution and i tried restarting my phone and turning on photo stream. when i turned that on my phone started reconvening my pictures and about 2000 of them started coming back in, but then the app crashed and they all disappeared again. i don't know now what to do those pictures are really important to me.

i haven't updates to ios10.0.2 yet i dont know if i should try to update now or if i should try to get my photos back first. will updating being my photos back or will they disappear forever if i do?? what do i do i really need those photos back.