What IS PMS? PMS is short for pre-menstrual syndrome. Pre-menstrual syndrome is a condition that causes severe physical and emotional problems--ones that interfere with your everyday living. Those problems range from violent mood swings to disturbed sleep. But before you diagnosis yourself, think again; PMS is pretty rare. In fact, only 2% of women get PMS and it hardly ever occurs in teens. You may experience a few of the symptoms, like breast pain or restlessness; but chances are it's not PMS.

What's the right age to get your period? There is no correct age for a girl to get her period. However, asking your mom and/or other female relatives about their first period might be a good indicator for when you may get yours. According to experts, it's hereditary. Another good indicator is your body. Menstruation usually begins two years after your breasts develop and one year after you develop public hair.

While many women get their periods throughout their teens, some may approach their twenties without a first period. This could be due to a number of things, such as intense physical training, but it's always best to have a doctor check out the situation, especially if you're over 17 and haven't started your period.

Why is my period irregular? For the two years or so of your first period, it's normal for your period to be irregular. However, if it continues to be irregular beyond two years (for more than three months at a time), then you should consult your doctor to be on the safe side.

Why is my period brown? Menstrual blood usually varies in color, from bright red to dark brown. If your blood is dark brown, chances are that it is old blood that has been in the uterus for a couple of days.

Brown blood can also be the result of spotting. Heather from "Help Me Heather," says that spotting can be normal. Many spot a little during ovulation, for example (and those who are on the pill may also experience a little between-period spotting). But in some instances, spotting can be an indication that there is a medical condition, like a vaginal infection. It can also be a sign that a teen is underweight or close to becoming underweight. Some underweight girls eventually lose their periods altogether and spotting is usually one of the first signs. But it's best not to guess about such things. If you believe you are spotting, then you should consult your doctor.

Why do me and my friends get our my period around the same time every month? According to Help Me Heather, some studies suggest that girls who live together or spend a lot of time together may end up coordinating periods. No one knows exactly why, but there is probably a chemical explanation for this phenomenon of synchronization.

Many of the theories about this center around pheromones (the chemical odor signals that serve as a stimulus for one or more behavioral or involuntary physical responses among animals of the same species). Much is still unknown about their influence on humans, but there are some indications that pheromones may not only control women's menstrual cycles, but also accelerate puberty and influence sexual orientation as well.

What is Toxic Shock Syndrome (TSS)? Toxic Shock Syndrome (TSS) is a rare bacterial illness associated with super absorbent tampons. TSS can even be fatal. To avoid TSS, change your tampons frequently, try to choose the lowest absorbent tampons as possible for your flow, wash your hands before and after you insert a tampon and never insert a tampon that has come unwrapped.

As for recognizing the signs of TSS, common symptoms include a sudden fever (102 degrees or higher), nausea, diarrhea, vomiting, dizziness and a sunburn-like rash. Toxic shock syndrome is a serious illness and if you think you (or someone you know) has it, please contact your doctor or emergency room immediately.