2 faint positive HPT but Negative Urine test at Doctor

Hi guys! So I did a HPT yesterday and it came back positive with a faint but visible line. Today morning I took another one and came back a bit more faint than the yesteday one. Went to the doctor and she did a urine test and it came back negative. I am so confused right now! My last period was on September 20! Any ladies here went through the same?