helpppp please

Ol

i am 8 days late for my period and I have never been this late... my last period was on 11/23 and i had unprotected sex on 12/15 but my bf said he didnt cum inside of me. I had stressful month bc of final and stuff and i tested 4 days ago and it was negative. I am so scared...my usual cycle is 28 days. should i test again tommorrow and am i possibly preganant???