Talk to Gynecologist on Gynaecologist Related

Hello, I have been trying to conceive but found out my eggs are not being made. Dr told me to take Lezra tab starting from 2nd day of my periods and then get trans vaginal ultrasound done on 11 or 12 day of periods. My question is, do i get ultrasound done on the same periods cycle that i take lezra tablet on? Or do i wait for next periods cycle to get it done? Someone said that tablet shows results in a month or so. Hence the confusion. Please respond asap.