short(ish) luteal phase

So my luteal phase, the phase after ovulation but before AF comes, has been a little on the shorter side since coming off the pill. About 10-11 days. I've been using digital ovulation tests to let me know when I ovulate. Here's my question- if I can take a FR test 5 days before AF is due, what happens if on that day I'm only 7 dpo? I feel like I've read that the horomones can't be detected until 9 or 10 dpo? I guess I should just wait to test, but I can never seem to do that! Just seeing if anyone else has been in the same situation. I have my annual GYN appointment at the end of the month so I'm sure I'll talk to her about it as well.