Did i test to soon or could i have got a negative already?

Thursday was a week since i had my trigger shot injection & yesterday (Saturday) was a week since i had the IUI procedure done. So just this Friday for the hell of it i tested which was 8 days since the shot & 7 days since the IUI & i got a NEGATIVE already. So im guessing the shot was out of my system already but could it have been just to soon to get a positive? Going to test again Tuesday & Friday of this coming week & see what it says. Thanks & good luck to everyone else ttc as well