Glad you are getting your surge again. Is it possible you peaked or early or late when you weren't testing? Every now and then there's a woman that does peak but the urine test doesn't pick it up before it's gone. They call it false negatives.
Clomid can be tricky. My doctor had me take clomid (50mg) days 3-5. We didn't rely on finding the peak. I was scheduled for an transvaginal ultrasound day 12 to evaluate the follicles. The follicle was the perfect size. The nurse gave me the hcg trigger (Pregnyl-10000units) in my right arm. Within 36 hours later I ovulated. I went home and inseminated according to my planned timings)
He told me he really preferred to work clomid with the trigger (he likes them as a package deal). If my follicle hadn't been the right size I wouldn't have gotten the trigger. Anyway, it was the lucky month for a bfp.
-I had a bigger(right size follicle on clomid) I didn't get multiple follicles like some women do.
- had many multiple follicles without it but only one was close enough to being the right size and still not the proper size to release a mature egg.
I think I took Maca and vitex in the months I wasn't taking clomid to help regulate hormones without clomid. One month I had the proper day 14 ovulation, but I didn't TTC so who know if it would've worked.
TTC #1: August 2017 - ICI BFP- miscarried @7weeks
TTC#2: December 2017- ICI, IUI- BFP! - Will induce @ 38 weeks (9/10/18 ) Can't wait to meet my sweet baby boy!