My last period was late and when it did come it was short brown and not a lot my period is always on time and last 7 to 9 days now im cramping?

Possibly pregnant. If you have been having unprotected sex then you could be pregnant. Women can have spotting or bleeding at the time their period was due and this can be implantation of the fertilized ovum on the uterine wall. You should have a pregnancy test as soon as possible. If you get bleeding with the cramping, especially if it is heavy, you may be having a miscarriage or you may have an ectopic pregnancy.