Using opk to hint at pregnancy

Because I spent so much $$$ on hpt's last cycle with my chemical pregnancy, I'm saving my last FRER for tomorrow when I'm more likely to show if I'm pregnant or not (I got a BFN yesterday with another FRER and I'm 11DPO today according to my BBT charting). I've been depending on BBT to determine ovulation because all the opk's I'd taken daily for the first 2-3 weeks of this cycle haven't shown even the faintest of lines, probably because I used fmu for it (I'm just not even going there peeing in a cup at work on my lunch break lol). I had a whole degree of a jump up in temperature two Sundays ago with an absolutely stark white neg opk that same morning. I mention that because this morning I couldn't help myself and did another opk plus a dollar store hpt that's only strong enough to detect hcg the day of af - got a bfn on the hpt, and for the first time all month I got a faint but noticeable test line on the opk with fmu. I know it's possible it's just af coming soon, but would lh spike so much in the morning for af when it wouldn't when I ovulated? I'm hoping it's an impending bfp of course, but I want to manage my expectations for the next 24-48 hours too.