So my lmp was 10/6 3 days after start I started taking letrozol 2.5mg , waited till day 10 had an u/s but my follicles…

So my lmp was 10/6 3 days after start I started taking letrozol 2.5mg , waited till day 10 had an u/s but my follicles were not big enough yet so I waited and had another u/s . Still not big enough so I started another round of letrozol 5mg. Had an u/s today, they are a few mm bigger but still not ready. Have to go back for another u/s Saturday... mind you I get bloodwork every time I go... I feel like a damn pin cushion because they can’t get my vain the first time.. so to end my rant I’ve been on this first cycle for almost a month and still haven’t ovulated. Has this happened to anyone doing fertility treatments??