Started letrozole; scared

Yesterday I started my first dose of letrozole. I’m extremely nervous. Wondering if it will work, if it does, am I really ready? They say no one is ever truly ready, but I’m nervous on if this is even going to work. I’m scared I’ll get my hopes up and nothing will happen. Then we are back to where we started. How successful was your round of letrozole? Did it work the first time or a few rounds?