I've always had my cycle on the 8th or 9th of each month but in august and september it came on the 4th and in september i had two cycles what does it ?

Change in cycles: "Periods" are roughly 26-34 days apart, depending on when one ovulates. The only "fixed" interval is between ovulation and the onset of a period. If under stress, you may ovulate late in a given cycle (day 18-20) in which case your period will be on day 32-38. If you ovulate on day 9-10, your period will be earlier. Period on 9/1/14 and ovulation on day 10-12 will result in a period on 9/25/14