Let's disagree to disagree. I still don't think that is her foot if you make a detailed observation frame by frame, but it doesn't matter:
1. Her pushing multiple buttons is not a psychotic action. She is doing it to buy time.
2. Her flailing her arms around is also an act of rationality since she is doing sign language.
Conclusion: this rules out the possibility she is on drugs and the acts are irrational behaviour.
So the REAL
question is: how did a perfectly sane girl end up in a water bin.