Last menstrual period was october 23, did a pregnancy test around dec 1 it was negative 2 weeks later around dec 12 positive. how many weeks ?

Cant say: You can use your last period to calculate using a free online due date calculator. That will give you an estimate. When you have your first sonogram you will be able to determine your gestational age more accurately.

From LMP: The duration of pregnancy is measured from the last menstrual period so you should count from oct 23, 2013. I hope that your are under the care of a doctor for the sake of your and your baby's health. If need be, your doctor can do an ultrasound exam to assess the length of gestation.