First time on here! 2nd round letrozole, my ultrasound on cd 11 showed I had 2 mature follies.i took opks but never got a positive:( went in for progrestrone bloodwork cd 21 and they showed I did ovulate! Still think we had good timing on cd 12,14,and 16. Now cd28 for me, bfn :(. But have had headache and neasous today, couldn't go to work even! Do you think it's a prego symptom?? Any insight from someone with letrozole experience?