The reason that your period is harder and heavier is because you missed two periods. Your body holds all the blood and excess skin and mucus etc. You missed your period because of stress or whatever the cause eventually your body has to get rid of all that blood. Thats why its longer and heavier.

I'm 17 and got my period late (16 months ago) but it only came 4 or 5 times throughout the whole 16 months. Should I worry?

My wife has her period every three months. Her one sister also has the same situation.

She used to take the pill to regulate her cycle monthly (prescribed by her doctor). My wife has struggled with her weight most of her life.

When she started training for a half a marathon, she lost some weight plus the regular fitness speeded her cycle to every other month.

I would not worry about it. Go see your family doctor to talk about it.

Hope this helps,

tomz