Possible Pregnancy?

So my last period was June 13th, & not even 3 hours before my period started I had unprotected sex, which caused me to start bleeding. I am afraid that I might be pregnant, but he did pull out, I just need some advice, its been 10 days & I am freaking out. Can you guys give me some advice please? My mom doesn’t know im not a virgin & im 17. Please help.