I expected more

Maybe I am being naive as to how hard TTC is going to be for me?  I had a monitoring appoitment this morning.  It is CD12 and I had one measurable follicle at 15mm.  The nurse said I have a couple others but they were not measurable (all under 10 mm).  A mature follicle should be at least 18 mm.  I was instructed to use ovulation predictor tests every morning until I get a surge.  If/when I get a surge, I am to go into the office asap for an ultrasound and they will instruct me on when to take my shot and we'll schedule the IUI.  I have another ultrasound appointment scheduled for Sunday morning (CD15), if I dont get a surge before that. I am a little disapointed.  I was hoping to have 2 or 3 measurable follicles.  I really want this IUI to work and although I know it only takes one, I also know our chances are increased if we have 2 or even 3 follicles.  I guess now, I wait.