I'm so confused!

Caroline • Ttc for 5 years now. We just lost our sweet baby at 18 weeks due to pprom. Heartbroken but have been given the ok to try again.
Ok. I went to the RE last week, CD 12, for a CD scan. I took clomid cd 3-7, 100mg.  My Dr is on vacation so I saw a random Dr. He did the US and showed I wasn't responding to the clomid because I only had 1 follicle at 8mm. He said I would not ovulate this month and could try again next cycle and they would up my dose. 
I decided to go ahead and use my digital opks because I have always had good follicle growth at that dose, I just ovulate late (CD 17 or 18). 
Today is CD 17 and I got a positive opk. Do you think the follicle grew large enough in the last 5 days?! Of course we are BDing all week. Just wondering if anyone else has had a similar experience?