How to edit a single frame without affecting all frames of animation in Photoshop CS5?

I can't figure it out why this is happening. I want to animate a logo frame by frame using Photoshop CS5 and everytime i change something in a frame, it changes all frames before until the moment i created a layer/shape. In result, all frames turn to be the same.

I'm thinking to use 4 layers and I would animate "interior" layer first and "splashes" in the end: 4 - splashes 3 - interior 2 - vector smart object (lock) 1 - background (lock)

Should I create a new layer for each new frame to resolve this problem?