Hi I am 24 years old and never been pregnant before. I know my period and my cycle but I don't track my ovulation and when it comes to ovulation I don't exactly know when I do or how to know when I do. My boyfriend and I had unprotected sex about 13-14 days after the start of my last period. I have been doing some reading about ovulation. I'm am curious about how long fertilization takes to happen. Does it take days or hours? I did not plan for this to happen and I don't know what to think or expect. I thought about taking the plan b pill but it has been 3 days since we had sex will it even have an effect at this point if I was ovulating when we had sex?

Once you ovulate, the egg may live for 24-36 hours. Sperm can live for up to 5 days. Fertilization would have to take place while the egg is still "alive". IF it is, it will implant between 7-10 days after you ovulate. That's the approximate time a HPT would work, which is why they recommend testing once your period is late. Before that any hormone might very well be too small to register accurately on the test.
So, if you know when you ovulate the egg could be fertilized within aprox 1-2 days and then implantation would be a week or so after that.