Clomid/Trigger Shots

So

My first round on clomid and first trigger shot. Wondering how long it took for the HCG to leave your body? I heard it takes up to a week but I took a pregnancy test (CD 15, 3 days after trigger and 2 after Ovulation) today and it was only REALLY faintly positive. Do you think that means trigger didn’t work as well? Or worked better? Or it’s normal? Aaaaaa! Wish TTC was easy!