"Testing out the trigger" ???

Brittany • Baby Mason is due on February 7th, 2017 ❤️ baby #1

I keep hearing this term.. and I don't think I understand. I took my trigger shot yesterday, and we inceminated today. So, my question is if I wait for 2 weeks to test, and if I get a bfp, it's possible that it's from the shot?

I dont understand what the trigger has to do with getting a positive test...My doctor didn't explain any of this to me...