no period but negative pregnancy test?

hello everyone,

my period was supposed to arrive between may 22nd and may 24th but it hasn't come yet. Took a pregnancy test on may 29th (7 days after missed period) and it was negative, took another one on June 1st (9 days after missed period) and it was negative.

I am sexually active and I use condoms, is there still a chance I might be pregnant even with 2 negative pregnancy tests many days after missed period? can it be that the changing weather/changing of the seasons affected my period? thank you