16 days late but all negative tests

So my husband and I just started TTC and I used birth control so I wouldn’t get my period. I got my period every 3-4 months for almost 4 years. My periods before BC we’re always heavy and long but generally never super late. My first period off BC was totally normal. Well. I’m 16 days late and have taken SIX tests randomly throughout the month. All negative. But I’ve never been this late! Is it because my body was use to not getting my period for so long? I don’t feel sick at all. Light cramping. ON AN EMOTIONAL ROLLAR COASTER and a big baby about everything (but I’m also a sensitive soul in general). How long should I keep waiting before I go see a dr? I have an appointment for something totally separate on Wednesday....should I say something then?