For those of you who have ever gone through fertility treatments/follicular monitoring maybe you can help me

Today I had an ultrasound to look at my ovaries and follicles to see if I am ovulating on my own.
I have had 2 medicated (clomid & trigger shot) IUI's in the past and we conceived both times but we don't know whether it was the clomid that helped or if I would ovulate on my own regardless.
My midwife just messaged me and said that I have 3 promising follicles, 2 on the right and 1 on the left that are all measuring around 1cm right now. I am currently cd13. She said that ideally they like to see the follicles around 2cm but she has seen women ovulate with follicles smaller.
My question is, my cycles are usually around 33 days and I am pretty sure I do ovulate on my own but usually it's around cd17 not cd14 like she's probably basing it... So could that be why my follicles are still only 1cm? If I won't ovulate for a few more days wouldn't they still get bigger over that time?
Sorry if this was confusing! I messaged her back and asked but sometimes it takes a day or two for a response and I just want your opinion as to whether I am thinking of that correctly. Thanks!
Re: Follicle/Ovulation question
Do they have any more plans to continue monitoring you for ovulation? Are you using OPKs or charting your BBT to see a temp shift?
When I took clomid before my follicles ranged from 18-21mm the day before ovulation.
I just wanted to clarify that they would still continue to grow. The way she worded it I was confused.
Since this cycle is just to verify whether I am ovulating on my own or not we are not doing anymore ultrasounds this time but they are going to check my progesterone levels at cd21/22 and will be able to tell if ovulation took place.
/loss mentioned/
TTC#1 July 2014
dx: MFI (morphology)
IUI #1 w/Clomid + Ovidrel Sept. 2015 ~ BFN
IUI #2 w/Clomid + Ovidrel Halloween 2015 ~ BFN
IUI #3 w/Clomid + Ovidrel Thanksgiving 2015 ~ BFP!!
hb 146 bpm at 7w5d
1/28/16 ~ began to say goodbye to our beautiful baby at 11w
d&c, followed by cytotec
TTCAL April 2016
IUI #4 w/Clomid + Ovidrel Apr. 2016 ~ BFN
IUI #5 w/Clomid + Ovidrel ~ CP
IUI#6 w/Clomid + Ovidrel ~ BFN
If they find I am not ovulating then we will do more monitoring and help my body to ovulate. If I am ovulating I'm not sure what my midwife will suggest.