my period is 17 days late (i was suppose to get it the 4th of july) ive take 2 pregnancy but they were like 2 or 3 days apart i took the first one when i was 3 days late and the second when i was 5 days late i think and they were both negative. ive been all over the internet trying to find out what could delay my period and i read something that said your period can sync with other people?? my best friend hasnt had her period in 3 months and we recently just started hanging out alot more because of the summer is it possible that i might have missed my period because ive been around her alot? or should i take another test to be 1000000% sure? please help