fruitloop part of the reason I stopped using opk's was because with my long cycle I was getting so many negative ones. Also, when I did get a positive one it didn't mean I was about to ovulate.
Last cycle was a very confusing one for me, I was taking my temps and occasionally peeing on an OPK. My temps were up and down all month, I got a positive opk about CD20 and I had patches of EWCM all month. Some days none, some days a little bit. I wondered if I was confusing semen with EWCM.
Having finally got to a normal cycle I've realised that the last one was anovulatory. I genuinely was getting EWCM all the way through my cycle (which means my body kept trying to ovulate). And my temp taking was correct it's just that I never hatched an egg in order for the temperature to go up. And the positive opk was just another indication of an imbalance in hormones. I got the LH surge, but didn't actually ovulate.
Feeling more confident that I've ovulated this month, all the signs are right. I had a week of EWCM, which completely dried up after ovulation. This coincided with my temperature rising. I checked that my cervix felt harder and closed.
I think the best thing you can do with a potentially long cycle like yours is to keep bd-ing every other day until you start to feel like AF is due. Then check your cervix position (to make sure it's closed) and you will then know to wait for a couple of weeks before taking a test.
Hope this helps - opks just aren't useful everyone.
(however feel free to ignore me, someone else on MN told me to stop using opk's and I didn't want to listen - I had to realise for myself that they weren't for me).