I'm sorry to hear you are having a crappy time ttc. It really is hard work - I remember the sex-ed chat at school and was terrified of falling pg by accident - well I know now that is rubbish!
It sounds like you roughly can pinpoint O day, so like Tiff said, try to do it as often as you can - sperm can live in a fertile environment for up to five days.
Sorry you're struggling at the moment Go have a cry, it's always good to acknowledge your feelings, and sometimes self-induldge in them a little. Have you thought of DTD every 2nd day when you don't have AF? It might be worth a shot, and would take a little of the pressure off trying to catch the right time...
Oh, mejane TTC can be so heartbreaking. I'm sorry you're feeling so down.
Longer cycles are a pain in the butt. I agree with the others though, maybe DTD every couple of days during your fertile time so you don't put so much pressure on to perfectly time it to O? Easier said than done - but perhaps worth a try...?
You're not doing anything wrong. Be kind to yourself - lots and lots of hugs.
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