I have been on the single rod implant nexplanon for almost two years now. I have been sexually inactive since 01/2016. I recently had protected intercourse on 5/22/2016 and a few hours later, I started bleeding. I thought maybe it was due to the sexual activity and hoped it would go away within a day or two. I had bled like this before during a pap exam and just related it to that but, it has been 3 days and I have not stopped bleeding. I'm beginning to think that it could be a period or worse, a STI.