Hi, I've Been On The Birth Control Implant Implanon For

Hi,
I've been on the birth control implant Implanon for 3 years now. And I have not had a cycle for 2 1/2 years now I'm due for a new implant this March 2017. I have been experiencing sharp pain that's been come and go in my uterine area for 2 days now. It doesn't seem like a cycle pain cause mine normally last longer but idk it might be different on this implant. Am I cycling because I'm nearing the end of my implant? Or is it something totally different?
Thanks,
Maddie