Conflicting pregnancy positive and negative tests

Patient: I was on the pill for two and a half years and came off it two months ago. after the first month i took a pregnancy test, which came back negative and went back on the pill. i tested again this morning and the result came back positive. what does this mean?

Doctor: Home pregnancy tests are considered very accurate.  Blood tests however are more accurate.  A simple blood test ordered d through your physicians office should  be able to determine if you are pregnant or not.  Once you receive the results of the blood test, there should be no need for retesting.