Soo on the 2nd and just recently again on the 9th i had sex with my boyfriend and he came in me both times but my period say it is to start the 10th its still not here ..

Im having like a watery clumpy type of discharge but im kinda unsure the meaning of it ..

I went to the store bought some test (ill show below) & it said 6 days sooner so i tested on the 11th it said not pregnant but how do i supposed to read those “# of days sooner” type test, and when to use them so, my period is set to be on the last day which is the 15th. should i test after in that time frame or take another sooner ? because if i need to test after i am thinking about on the 16th.