When did you think you would have ovulated?
Do you know why you need IVF or is your issue unexplained?
I have not pregnyl before but have a friend that is currently testing it out of her system. I'm sure she said 1 week for a BFN. Would that be about right?
If its about a week and I guess having had several it could be longer for you then there could be a day or 2 with a BFN before the BFP would show right?
Best of luck. I hope its a BFP within a few days.