How long will it take to show signs of the swine flu?

okay so one of my teachers at school had the swine flu and was only gone for 2 days. 6 people in her family had it too. Then another teacher comes to the door and is sweating like crazy and said he felt horrible so he was going home. THEN I go to another town that has a lot of it and the schools closed there. Just in case I picked it up, how long will it take for me to start showing signs of it?