OK, so i'm 15, and have never sex before, so of course im not pregnant. But the last period i've had was in march.Usually my periods are quite heavy and last 7-9 days. They started when I was 11 and arent usually on time, like I have one, then in 2 months I have another, then in 3 weeks i have another. But its been 5 months so Im kinda scared. :C Can anyone help please?