If you had your period on the 7th and you started bleeding a week later (around the 14th I presume) and you are still bleeding, you definitely need to see a doctor. While some bleeding (implantation ect..) can happen in early pregnancy, it doesn't last that long and is usually only spotting.
it is NOT necessarily an early sign of pregnancy, but it can OCCUR during pregnancy...I agree 100% with Victoria, please see a doctor. If you're pregnant and bleeding heavily enough for a flow you need to get checked for a possible miscarriage, and if you're not pregnant you need to figure out why you're bleeding again so soon....good luck.