Going to photo roll should always show the latest picture/video
If you look at the photo roll in camera app, go back to taking picture/video and then revisit photo roll it'll be at the old position of the previous picture/video you looked at instead of the one you just took and you have to start swiping right.
The same behavior is visible by simply viewing some existing picture/video in the camera roll, pressing back in top-left corner and going back to camera roll again.
Edited by Jami Kettunen