In my opinion you shouldn't be able to get pregnant. You don't ovulate until a week and a half after your period. Sperm can live up to 72 hrs in the vagina. Your period most likely flushed it out. I also agree with Clysta, if you are concerned then safe sex is always the way to go. Having a baby when you are depressed isn't healthy for either of you.
It's too late for an EC. It's meant to be used immediately after sex, not 3 days later. Yes, there's a chance for pregnancy. It doesn't matter if he doesn't ejaculate in you, it's still there - pre-ejaculation DOES contain sperm and WILL get you pregnant. No reason to be scared, you should have known these risks before you engaged in it. Wait two weeks and take a pregnancy test with first morning urine.