First IUI

Hello guys

we are doing our first IUI this month, any day now. I am taking Femara and getting the trigger shot before the iui. I am at 1.4 for my follicle on day 7. I usually ovulate on my own after the follicle is 1.7. 1.4 seems large to me so early in my cycle. Has anyone had any experience with this. Does it matter when my follicle matures or just that it does. I am a bit nervous to try IUI but very hopeful. Any advice, experiences? I welcome all!!!