Up to 20 days late now

Michelle • Engaged to my best friend 6 years together in 2015 ?ttc mexican, white &Black baby
My periods went back ok track on July since before July I had just stopped taking the pill and the Implanon. . I recorded each period and now October 2014, no period this whole month ..is thought I could be pregnant. .I've only had sore breasts and dizziness I felt during work ..but my test came out negative? will I be having no periods like this because I was on birth control for so long ..?