I've been on Nexplanon for just over 2 years now and have had no period since going on it. I never actually had sex while on it (using it mostly for the no period thing but it was also a backup in case sex happened again) until mid July. We used a condom and it broke, but I thought no biggie since for all intents and purposes the no-period thing had been a good sign that it's probably been working these past two years.
Even so, for the past two days (~3 weeks after having sex) I've had weird spotting/period symptoms for the first time. I had the cramps I used to have, but the only bleeding I had was minimal and faint pink/mostly brown, just like what my period usually looked like at the end of my cycle. I figured fine, whatever, I'm approaching year two so my period is probably going to start coming back, but then the internet got me worried about implantation bleeding. The rod is still in the same place it's always been and it doesn't feel broken so I don't know what's up. I know the likelihood of it being a pregnancy is slim, but I'd really appreciate some assurance/feedback since I've never actually used Nexplanon for sex and now I'm worrying that it's been working wrong this whole time