Why would i get a positive ovulation test one day then negitive results for 6 days then another positive result that only lasted three hours?

Depends: It depends on the test you use. Sometimes using concentrated urine( like the first specimen of the morning) may result in a false positive test. The test measures an lh surge but may have false positive results around the time of ovulation. Perhaps changing the type of test may be helpful if you are not pregnant this month. Good luck!