TTC help

Hey I was wondering if anyone is in the same situation I’ve been getting positive opks on day 14 as well as textbook EWCM but not having any luck conceiving where are we going wrong ? Been off the pill and had a 28 day cycle for about 3-4 months now.. had bad cramping last cycle around 10dpo so I thought that was the month but then got my period! Maybe there was a problem implanting? Trying pre seed this month see how it goes