**EDIT** would a seven year old say this? "Tell your girlfriend to use spermicide
. That should reduce the risks, and yes it is Always possible to get prego with or without the use of a condom."
This cannot possibly be a 7 year old, but what the hey..
When I first got my period (at age 11).. there were no signs, it just came. It wasn't until later that I got cramping, etc. I began to develop very early, but the period did not come right away. Don't worry about it.. you are probably not due for it yet (although it can happen), but even so.. the first time there will probably not be very much blood and you will probably not bleed for a long time. It will take a while before you get it the same time every month (if ever). If you are lucky it won't last a week. Thankfully, mine is here and gone in three days!
P.S. For all of those who think you have to be older to get your period.. it just isn't so. My mother was 9 when she got her's. I also knew a little girl who was 5 with the ovaries of a 16 year old. For some reason her female organs developed early. That was a very difficult thing for her mother to have to explain to her I am sure. Children are not as naive as you think and they can't be. Girls are developing a lot faster now...