I had the same thing happen to me. I had positive tests at home and a negative at the Dr office. I requested a blood test and it came back positive, my level was in the 500s.
They should have done a blood test. I would request that to be sure.
The clear blue digital is just about the best you can buy OTC at least that is what my doctor said. They had to do a blood test on me bc mine came back positive but theirs didn't.
Were you using first-morning urine at the doctor's also? If not, it might have been too diluted for the hCG to register. Test again tomorrow with a home test.
Sometimes dr's tests aren't as sensitive as the over the counter ones. I suggest requesting a beta hCG test. Looking for a quantitive number not qualitive.