Missed AF but negative test

Gina
Been TTC for 3 years. Was on the depo for 5 yrs and we were told that can make getting pregnant even harder for a few years. Anyways, my period is almost a month late- took 3 test all 3 negative. I keep feeling like my period is coming but then another week goes by.  Is it possible I am pregnant? Or stick to what the test say and hold out for my next ovulation to keep on trucking.
Thanks!