Ladies I could use your help.?

I got my BFP today well here is the thing im confused on I have my first dr appt is on the 16th but till then Nov 19th was my last normal period and dec didnt have anything then Jan 1st had a very lite period for a few days was due for another period around the 25 or so and never got anything And around dec I sooo could have thought I was preg so anyway I could either be 12 weeks or 6 weeks