Please bear with me, this is all very new to me. I need some advice from some friendly POAS fans, and from my lurking in the past week I think I've come to the right place

This is my first cycle ttc (trying for #1), after 12.5 years on BCP. At first I was going to wing it for a bit, but then I decided I might as well start monitoring things. Can't be too careful considering I'm already mid-30s.

I suspected I might have O'd around CD13, based on anecdotal signs (CP/CM, tiny bit of random, unprovoked momentary spotting). Since then (now CD26) I have had the standard range of post-BCP/PMS/pseudo-pregnancy symptoms. Ridiculously optimistic, I know, and I take it with a grain of salt.

Now here's the mystifying part. At some random point just after CD13, I bought and used a dollar store OPK just to try it out. There was no test line at all. Not even anything remotely squint-worthy. Some online research told me that some women never get a positive or even any kind of line on an OPK, so I gave it up. I started temping shortly after that, and my levels have been fairly even, but of course I have no way of knowing if they are pre-O or post-O for me.

Yesterday afternoon (CD25) I felt some menstrual-type cramps, which are standard for me. I even went to the bathroom and checked, but there was nothing. Just for kicks-and because they were hanging around and seemingly doing me no good-I decided to use an OPK. This time I had a clear-as-day test line, but definitely not nearly as dark as the control.

Figuring my pee might have been nice and concentrated, I put some from the same sample on a dollar store HPT. Nada.

I'm not looking for an answer as to whether I'm pregnant or whether I O'd, because I know it's impossible to tell. I'm just wondering what to do now. Do I continue with the OPK and see what happens? Do I use an FRER tomorrow morning (CD27) just for fun? (Yes, I can handle a negative.) Or do I just stick with temping for now?

What do I pee on next and when?

Thanks for all your input!