Any regular cycles girls have a odd month?

Hi, looking for some feedback- I've had regular 27 day cycles for last 5 cycles, with lh surge cd14 or 15. Now I'm currently on cd18, with no indication lh surge coming, line has stayed very faint (I test 2x daily). Could I be just having a long cycle- i.e. Keep testing or is more likely I just won't ovulate this month? According to glow, fertile period ended yesterday and AF should be due 1/16-1/17. Thoughts? Feeling so discouraged.....