Is it possible to implant late?

Kat

I took a test at the day of my "missed period" or 14DPO and got the faintest positive. So faint my husband told me it was negative. Well today is 16DPO and you can definatly see the line but what im wondering is so many pregnant women get a dark positive at 14DPO. Is it possible I just implanted late? I know for a fact I ovulated 16 days ago.