It does not have to be 14 days at all. From charting I have discovered that my luteal phase (the time between ovulation and AF arriving) is 12 days. Some peoples are longer, some are less. Any length from 10 to 16 days is considered normal, less than 10 days and the body may not have time to prepare to carry a baby so pregnancy may not happen.
Are you sure you definitely ovulated 7 days ago? If you did then the pain could possibly be implantation (hopefully) but not definitely of course. Otherwise if this is ovulation then yes you may have to wait any time between 10-16 days for AF to show.
This is where temping comes in really handy. Before I was temping I was BDing at all the wrong times cos I have a 29 day cycle usually, were getting all our BDing done between days 13 and 15 presuming that was half way through my cycle and when I should be OV, I dont actually ovulate until day 17 usually so I was always missing the egg. I have then have a 12 day wait rather than a 2WW.