Advice please

Not sure when my last period was, don't keep track like I should! Me & my boyfriend have unprotected sex but we do the pull out method I am aware that it does not work all the time, i took a test 3 days ago & it said negative but I still have not gotten my period this month! Should I give it a few days & take another test or just wait it out. Any advice would be appreciated!! Thank you in advance