PLEASE HELP?? VERY CONCERNED ABOUT POSSIBLY BEING PREGNANT!!!?

okay so first off heres my symptoms: headaches, cramps, sore breasts, slight nausea feeling and yeah wired but frequent bowel movements. Next off I have been taking the same birth control for two years and never got these symptoms from it. My period is due in a week. I was nine hours late on one of my birth control pills 2 to 3 weeks ago. I took a test today and it said negative but it is also very ealery.... I am really worried if I am or not. I heard brith control pills can be very dangerous to a baby but I don't want to stop taking them in-till I know for sure whats going on with me. help??