Can you get pregnant during fertile window?

Ok so I need help y'all... 
My boyfriend and I had unprotected sex two days in a row. He used the pull out method and reassured me were fine but I was scared and took a plan b just in case. I was looking up if I should take another one since we had sex TWO days in a row (ya know since the sperm can live inside us for up to 5 days) I really don't want to but I NEED to know if one is enough.. Also I looked up definitions online (just joined <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">eve</a> and have never heard of a "fertile window") apparently on a lot of websites it says that a woman can only get pregnant when she ovulates! So basically what I'm getting off of these websites is that a woman can have sex any damn time she pleases until five days before her ovulation takes place?! Like wtf!! Is this true? If it is let me know please.. This is mindblowing to me lol also I was in the beginning of my fertile period when my bf and I had unprotected sex.. So does that mean I have less to worry about?  UPDATE** fertile is the same as ovulate😑😑😑