I've had two periods in less then a month. is this normal? i am 22 years old, i have had 3 boys.

It can be: Periods can frequently be 3-5 weeks apart (with an average of 4 weeks). It is possible to have two in the same month and be completely normal. Also, some months are longer than others which may account for two periods in one calendar month. Keep track on a calendar and see your doctor if they are consistently occurring less than 21 days apart.