Implant in arm? Birth control!?

Lilly • Im Lilly (: i have a son Ryder! & Im in love with his daddy Colby!
I have a little boy, Ryder. I've been breastfeeding! But it's time to get on birth control and I've been doing the patch but I just hate how it makes me feel & it gets dirty, so I was talking to my fiance about the implant in the arm for 3 years because I don't plan on having any more kids anytime soon I'm only 16 ... but it was a year before I had ever gotten pregnant with my son! So I'm guessing it's kinda hard for me too get pregnant? But what I need to know is the implant going too make me go infertile!? I've heard how some girls do....