Im 17 I've had my period and its pretty irregular but I just started having sex and me and my boyfriend usually use condoms but we didn't twice. My problam is I haven't started and now I am having horriable cramps in my lowere abs. IM FREAKING OUT!!

Well not using protection greatly increases your chances of pregnancy. I would take a pregnancy test, only way to know for sure. Maybe call your dr for an std screening too.

The cramping could very well be your period getting ready to come.

If you don't have your period in a week or two, be sure to test using first morning urine.