Cd 9 follicle check on clomid

Sy
Hey everyone! I'm pretty new to posting but I just wasn't sure what to make of my ultrasound follicle check today!
Okay, this is our first round of clomid for a luteal phase defect. I'm on cycle day 9 and had several follicles but only 4 that were big enough to count, according to my doctor. On the left side, I had 3 at 13mm and on the right side, 1 at 18mm. 
Are these not big for only cd9?! Like I said, im new to this, so I might just not know what I'm talking about. Did any of you experience something similar? Thanks in advance!!