period 9 days late

So my period is 9 days late this never happens it's usually always early and I get my period every two weeks me and my boyfriend have unprotected sex he pulls out yes I know that's not smart but it's just what we do so please don't comment and tell me I'm being silly by anyway I took a pregnancy test 2 days ago the clear blue ones since they are supposed to pick up early pregnancy but tested negative 2 my boyfriend said he has actually came inside me a couple times so there's a super high chance I thought I could have been pregnant but apprently not I don't know what to do my period still hasn't come any advice? 
Thanks girls in advance :) xx