
what Jen says... the LH can rise and fall through out the folicular part of the cycle, giving faint, or 'medium' lines on opks... it's only when it really surges before O that it'll show a line as dark or darker than the test line.
My guess would be you didn't O yet, so don't be so hard on yourself... and for goodness sake don't beat yourself up about not wanting to BD - you're not a robot and if you miss this month, there's always next month.
Good luck!