Positive urine test, negative blood test?

So I was getting positive results on urine tests and went to the doctor. I got a positive result on the urine test there so they did blood work (they did the one where it tells you how much HCG is in your blood), and it came back negative. I’m so confused and upset y’all, I got positives on blue dye and pink dye both. I’ve had some symptoms, missed period, etc. has this happened to anyone else? Even my doctor is shocked. They told me if I don’t get my period within a week to come back and they’ll do another blood test. I wish I could get some answers! 😔