Really great start! My issues with the piece lie in the foreshadowing. The blue-haired girl looks like she is INCREDIBLY tall in comparison to both the other girl and the door. To get the effect on point, I would make the camera more fish-eyed, and make the blue haired girl's foreshadowing more exaggerated around and closer to the camera.
The coloured also clash somewhat, and they seem more disjointed from the background than popping out from it. Making the camera lens more sepia or grey would really help with this, and realistic elevator lighting would also really help the characters become part of the scene.
Awesome work, and I hope my points help out!