How fast can i find out if im pregnant? its only been a week!?

Question

i know i asked this question alot im just stressing to much. if i get my period every 2 months or a little less and by saturday i dont know if it ended cause i had very light brown stuff , later that evening i had s*x and my boyfriend came in me , i want to know if im pregnant or if its possible since i dont get my period like others?

Answer 1

And its only been like two weeks..

 

Answer 2

What is the best test out their that I can findout sooner???