Looks like possible O on CD#18... "ish"

I say that b/c of the W cm, ferning and +OPK the day before (+OPK's can happen 1 to 1 1/2 days after your darkest test

). your temps have kinda been going up but not in any real definitive way. So that's what I'm not 100% on this. Sometimes your body can be gearing up to O and all the hormones are in place, you get the +OPK, temps drop a bit, CM is there... But stress Vito's what your system was working on and O doesn't happen. But! Your body will try again and you could end up w/ a longer cy b/c of it.
Also.. This cy, it could be that you are just not going to O. It happens to just about everyone once and a while for one reason or another. And another explanation is that you did O but you could have a minor hormonal issue like low progesterone... But unless you have been TTC for about a year (and b/c of your age) will only test for such things after a year of TTC (although I've heard some younger girls say they got testing done at the 6 month mark). If your Dr. suspects PCOS, it could be a problem w/ one of the hormones your ovaries produce to keep your cy's running normally.. Progesterone is produced by your ovaries.. So keep that in mind.
HTH!! Good luck this cy!