Ive had my Implanon Implant for at least over five years. I know I needed to get it removed, but could not afford it. I have had two periods . Month for the least few or more months; however within the last two months I have had unprotected sex. For that past month I have not had a period. I have taken one PT a week ago but it came out negative. Is there a chance I could be pregnant?

Sure. Periods and sex with no protection = babies.

Even with protection there's a chance of pregnancy every time you have sex. No form of birth control is 100% effective.

Having said that, it is possible you're pregnant. It may be that you tested too soon. How late is your period? It should be at least 2 weeks late before you test, and you should use first morning urine.