Okay ladies, I could use some help! Any ideas why I can’t conceive?

-Been unsuccessfully TTC for 7 months (this is month 8)

-28 day cycles EVERY month. Never been one day early or late.

-I get a strong + OPK every CD14

-My husband has had a SA, everything came back good

-I got a CD3 AMH/FSH/Estradiol test earlier this month, everything came back good/well within normal range

I just don’t understand why it hasn’t happened yet! My husband and I are both young (he’s 26, I’m 25). We’re both active and healthy. I’ve been also doing yoga the past few months and we’ve been eating very healthy. What else could possibly be the reason why we haven’t conceived? I was worried it could be endometriosis or ovarian cysts (despite not really having any of the symptoms), but everything I’ve read indicates my CD3 results probably would have come back with elevated estradiol and possibly Low AMH if that was the issue. I’m getting a 7 DPO progesterone test this month to confirm ovulation, but I’m pretty sure I ovulate since I get a strong positive OPK on the same day every month. I’ve researched everything. I sometimes spot brown (very lightly, only there when I wipe) 2-3 days before my period. Is there any way that’s causing an issue? Any help would be appreciated...I’m just feeling so defeated.