My friend is being really selfish!?

Yesterday my friends parents were killed in a car crash, so I thought I would invite her around my house to play the wii and do an exciting jigsaw puzzle. Responding to the invite she cane round. She wasn't very happy for some unknown reason and was dampening the fun, I screamed at her for doing this as she was getting really annoying. All of a sudden she burst into tears and threw a packet of roast chicken crisps into my private area. Do you think she is on her period or something because she seemed a little upset. I have no idea why.