[Arcenciel]

Every girl's period cycle is different, but for most women it's about 3-5 days I believe. I get mine for nearly a whole week and sometimes 8 days...but that's because mine is super heavy. Every girl is different, but that's the average.

As for the next time you're going to get it...I think it's about a month until the next one. For a while it will kind of be a surprise until you get to know your period cycle. Just keep pads or tampons (or both) in your backpack with you and maybe carry one with you in your purse so when you're out and about you aren't left with no backup. Also, periods can be super irregular for the first while (year or so) after a girl starts getting it. The best way to know is just to be prepared. A lot of girls mark their cycle on the calendar when they get it and then count the days, so that they can better predict their period. Give that a shot and see what you can come up with.
Congrats on getting it, by the way! I was really excited but terrified when I got mine. You've now got it until you're like...50...so enjoy it now while it's still new and not a pain in the bum!

Jen