I am having random, sharp pains in my arm where my Nexplanon implant is. The pain shoots all the way down into my hand and up into my shoulder. I typically gently rub the implant and the pain slowly subsides. I am also having head aches and lower abdominal and back pain. What could be causing this? Is it a common side effect of the implant? I've had it for over a year now and have not had any trouble with it until the pains started about 2-3 months ago? I have not injured my arm recently either.