I am 20 years old and had a pacemaker implanted almost eight months ago to correct SVT and A-Fib after two unsuccessful cardiac ablations. I began taking Depo Provera about six months ago. About three weeks ago, I began experiencing sharp chest pain on almost a daily basis; however, it generally subsides after 20-30 minutes. During this time, I can also feel my heart racing. I have heard before that Depo can mess with your heart and lungs. Is this a possibility?