noticeable, daily nausea, at least 1 horrible headache a day

I am 24 years old and am now 9 days late for my period. I have cramping in my lower abdomen (not horrible, but definitely noticeable), daily nausea (no vomitting, but constant), and I get at least 1 horrible headache a day for the last (almost) 2 weeks.
My boyfriend and I regularly have unprotected sex, and use the "pull-out" method.
I took a HPT this morning but i believe it was defective.. nothing appeared in either window!
Should I take another test tonight, wait a few days to take another, or just wait for my period??
My has been very regular since october, and I have been keeping close track so i know that I am definitely late.
Help!