I hope i am not pregnant.

I usually have regular periods each month that only vary one day. Im 3 days late, almost 4. I had unprotected sex around 3 weeks ago. He pulled out and checks often in the middle of sex and never comes inside me or pre-cums...(it was stupid i know). I started spotting dark brown discharge for a couple days a week later. Right now im having a bit of white discharge. I dont have access to a test right now...please let me know your experiences...i am beyond terrified. Thank you.

UPDATE : 5 days late now, took a test and it was negative. I have more tests..when should i take them? And how common is a negative test (wasnt my morning pee) ???