Microwave Etiquette ...

Had to share the most awkward thing that hapopened to me this morning..
So I go downstairs on my break.. and there are 6 microwaves downstairs to warm up my food in.
I see one is free so I put my food in.. and here the bottons are pre-set so - I pushed 9- which set my food to cook for 4 minutes.
I go to the cafe to grab a tea real quick - which litterally took me a minute- and then went back to my food.
I open the microwave because i knew it woud be done- and find someone elses food there..
The girl behind me goes - "Ya that is mine, I put your food over there"
And I see my tupperware over on the counter... confused.. I pick it up and go to the elevators and realize my tupperware is luke warm.. like almost cold.
Then I realize.. she not only.. took my food out... but took it out before the timer had stopped to put her food in?
Random.. Rude.. and Wierd...so I had to go abck and heat my food again...

THOUGHTS?!