Period two time in one month and not on birth control

Well, it depends on many factors like your usual menstrual cycle length, the ir/regularity of your previous periods, if you had unprotected sex or not, if you've been stressed, had a cold or something.....

Some girls cycles do last 21 days while others last 30 days. My cycle lasts 24 days but I had moment when my period would arrive on the 22nd or 23rd day of the cycle, these things just happen.

If you happen to experience any other irregularities, you should see your doc.

i have gotton my period twice this month first started on the 1st ended on the 6th then what da no again on the 13th.n still have it.... what is goin on i have a partner for two years n id have sex everyday even w/my period.could that effect it? im scared i dont take birth control n my opion i dont think i can get pregnant why havent i yet.... n its weird its not slowin down its pretty heavy but then sometimes i have nothin there when i go the b-room. can someone pleeeeeeeeeeeeeease tell me what could goin on???????