Hey, My first question to you is have you ever had sex before? My second one to you is had you missed your period previously and if yes, is this the norm?
I've been through a similar situation where i've had all those
pregnancy symptoms ( the nausea, lightheadedness, tender breast nipples and total lost of appetite) then three weeks later, I got a brown \"flow\" that totally freaked me out. My husband and I went to the Emergency Room where a sonogram confirmed that I had a missed abortion. I didn't experience any bleeding prior to this so i was totally devasted to learn that I had lost a baby I didn't even know I had!!. Anyway, my husband was very supportive ( he shed a tear or two ,also); I was given a D&C ( my uterus was scraped to removed the fetal remains) and was sent home.
So please do not be scared; go to your community cliic or your local hospital so that if you are indeed pregnant and miscarried, that you can get the correct care and treatment. If you find out that you are not pregnant, then you need to see your family practitioner so he can tell you what is going on. Best of luck!