25 liter glass bottle upside down. Inside the bottle 12 l. water. negative pressure

25 liter glass bottle upside down. Inside the bottle 12 l. Of water. The negative pressure. The bottle jerks down and protrudes 35 cm. upwards when air pushing inside bottle.

https://youtu.be/vzblIc2OaSs

Why does the bottle move first downwards and only then upwards? When air is pushed inside the bottle where is under pressure.

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