I started on birth control on oct. 30th, I only took a total of 3 days. I haven't had a period since Oct. 29th, which makes me 16 days late and 2 negative. Pregnancy tests

You started bcp the day after starting your period?
I suggest getting a blood pregnancy test from your doctor. Its possible you are experiencing a normal hormone shift due to the pill, etc. or that your pregnancy is not yet registering on urine tests