Hi there. Unfortunately no medical tests are perfect. There are possibilities that tests can give erroneous results. The same thing applies with the case of herpes also. Specific blood test which is used to test herpes can go wrong. However, sensitivity and specificity of the test ranges between 91-99% according to the type of test conducted. ELISA test is considered as the benchmark of finding the presence of HSV. In ELISA, a result with a value greater than 1.1 is considered to be positive. If this is the test done already, you can prefer doing other tests. If you have not had any history of herpes outbreaks or haven’t received any positive culture or PCR for HSV infection, you should find the index value from your test results. False positive results are announced if your result is lower than 3.5. If this is the case, think about taking other tests like Western Blot. Western Blot is another test to find antibody content in blood, which helps to find presence of virus. Anyway taking of contraceptive pills will not affect contraction with virus. Hope my answer helps. Take care.