Letrozole/Femera CD 3

Kristy • 29, Mama to miracle baby girl after 3+ years of infertility, Dog mom, Speech-Language Pathologist, TTC baby #2
Hi ladies! My husband and I have been trying to conceive for just over a year. I'm 26 with 1 ovary (right ovary removed @ 10 years old due to severe, ruptured cyst). 
So today is CD 3 and my first round of Letrozole/Femera. My doctor prescribed me to take 10 2.5mg tablets today. That seems like a lot! I've been reading people taking 5 or 7 mg, but never over 20mg in one day. 
Has anyone taken this dosage and had results/side effects? Also, I'm scheduled for blood work in CD 4, 10, and 21, and also have my HSG procedure and transvaginal ultrasound  on CD 8. I'm super nervous about those, so if anyone has any experience or advice, I would greatly appreciate it!