woh, what just happened!?
The frame by frame work was great, I much like the part when she stretches her eyes. I don't know why but that stuck out the most. The posters on the wall were an amusing easter egg, and a nice touch to the environment.
The art was very simplistic, the lines and colors worked very smooth. Although I do enjoy seeing some shading, I don't think it was necessarily.
"A short thing I put together in a few days, experimenting with voice acting & audio mixing."
I'll bring some attention to your main focus.
The only thing I see that could use improvement is your voice. Shout voices are really hard to grasp, so it really wouldn't be fair to fixate on it. Sometimes it helps to let adrenalin flush through you, to the point where you almost feel angry when shouting. Almost convince yourself that you're taking the place of the character. At the risk of sounding corny, BE THE CHARACTER!
Aside from the shouts, the sleepy voice I felt was nailed quite well.
As far as audio mixing, it was very basic. It held a great balance and you didn't add too much, or not enough. You seem to have a firm grasp on mixing your audio.
Kudos! Over all it was very enjoyable and entertaining. Great job :)