Negative blood test, then positive urine tests?!

Jessika
I was almost 2 weeks late for my period on March 9th. My doc had me come in that day to have blood work done. HCG levels were only at 2. I can handle that. But then on the 15th, I had 1 positive urine test. Next morning, another. Took 2 more later that day (march 16th) and of course both very positive. I called my doc and they have me coming in for a confirmation. I have no clue how far along I could be. Is this a common thing? Being 2 weeks late, having a negative blood test, then positive urine tests? It's weird right?