Positive to negative ?

Cari

Monday I got a very obvious positive. This morning I went in to the OB office to confirm pregnancy. And their test said negative. The nurse said their tests might just not be as sensitive as the one I took and told me to take another test in a week since it’s still so early. Today is 14dpo. She said not to worry because mine said positive and it’s very hard to get a false positive. Anybody have this happen? So weird the test in office was negative