Rinnie, I have a friend who had implanon and she some how managed to squish her arm and fractured the implant. She then developed a sore arm and really sore BB, she did not mention cramping. She was getting too much hormone, she insisted the Dr change it, much to thier reluctance. But her symptoms went away after.
I had Implanon once, it was good for 18 months, no AF. Then I had irregular AF, it got annoying so I went back on the pill.
Anyway, I hope you get what you are looking for.