They did a urine test and told me it came back negative, but then the doctor who gave me a pap told me the test could have been wrong because its weird for me to have all these symptoms. I'm thinking if my period doesn't come by the end of the month something is going on.
And if you're constantly thinking about it, you're stressing yourself out over it. I've done that to myself when I was your age, when I lost my virginity. I didn't start having normal, regular periods til I was about 17 or 18.