I recently took a pregnancy test and it came back positive but then i realised it was out of date. so i went and bought a new one which was negative. ?

Can retest or wait: She can repeat a urine pregnancy test next week. There is no need to repeat it sooner than that. If the reason she did a pregnancy test is because of a missed period (when normally her periods are always regular), then she can also just wait for her next monthly period... and if that period doesn't come, she can do a home pregnancy test at that time. If her monthly period comes, no test needed.