Never had sex before so im 100% not pregnant so what could be the cause of having two periods a month (2 weeks apart) i'm 22 years old and this is new?

Menstrual cycles: It is common for young women to skip a period and have irregular cycles. It is also more likely if you are very athletic, gain or lose weight, using birth control pills, or have an eating disorder. I would track your cycles to see if it happens often and see your doctor if you notice that it becomes more irregular.

Ovulation: Bleeding can occur at around the time of ovulation. An-ovulation can result in irregular and unpredictatble bleeding.