Nature I just wanted to put my story across.
I can see that you use a fertility monitor to track ovulation but that doesnt mean that you are ovulating it just means your LH rises.
I've been ttc for 20 months now (Im 26 and dp 30) and completely believed I was ovulating, I had cramps around cd 14 always had a 28 day cycle and positive opks but blood tests showed no ovulation! Im now on second month of clomid and ovulated last month.
Your GPs appointment wont be very exciting normally blood tests and a semen test for your other half. I had to have 3 months worth of blood tests.
Day 21 test needs to be 7 days before your due AF any other time and it wont show ovulation sufficiently (A day either side is fine), this will be the one that confirms ovulation.
If a problem shows up they will put you through to see a gynae doc.
Gynae doc will need to see you both and will talk you through everything they will probably ask for more blood tests, for you they may carry out an internal scan on the day to check for any lumps etc and they may also book you in for a HSG (a solution is injected up into your tubes and you are scanned to check for blockages).
It took 8 months to get from gp to gynae to clomid!