It means you should go to the doctor.

It's not uncommon for young girls to miss periods completely. I'm 17 and my friends still sometimes miss thier periods some months. It just means that your body is still adapting. It's really nothing to worry about... I would just let your mom or a doctor know and they'll be able to help you out in case you need to take some medication or something to make your period more regular. Don't stress...I promise it's completely normal.

Thanks!

I started at 13 and only had my period about once or twice a year. The doctor said not to worry, my hormone levels were out of whack because I was still going through puberty. I'm 19 now and the only reason they're regular is because i'm on birth control. So just check with the doc- she might do a blood test to check your hormones, but that's probably just to make you feel better. You're fine:)

First of all - just to confirm - have you had sex or have you been fooling around with a lad?
If not then you can rule out pregnancy - because to get pregnant you have to get semen (come, sperm, ejaculate) into your vagina.

Then as everyone else has said it can take years for your periods to settle into a regular cycle.

However, somethings can cause your periods to stop:
*eating disorders (such as anorexia, bulimia, etc)
*severe athletics (at any age if you are training exceptionally hard it can make your period stop as you don't have enough resources left in your body to support a pregnancy)
*severe weight loss or gain

it sounds perfectly normal and I am sure it is, but I would suggest a quick trip to your doctor just to let them know, that havig started your periods they have at present stopped.
That way if there is a problem - such as hormone inbalance - then you and they are ahead of the game, and can treat the condition accordingly.

Go to the doctor.

When I got my first period, I was 13... And then I didn't get another one for like, 5 months!!!

I've been getting my period since before my eleventh birthday, and I still only get it only a handful of times a year. And i'm almost fifteen.

Periods normally don't regulate until we reach age 19 or 20 :)

mine ended up being an unusually long cycle, probably due to my size and weight. Off the pills, my cycle is about 35-40 days long. An average cycle is 25-30 days long, but any variation can be heatlhy; as long as you are well, and it doesn't adversly affect your life :)