6 week check up question

So I go Wednesday and I've never ever been on birth control, I'm terrified of it. I'm scared of all of them, I'm scared they'll make it harder for me to get pregnant when I'm ready for another, or if it's an implant I'm worried it'll move.. I was honestly just not going to be on anything and just track my ovulation and use condoms. I just don't see how birth control is healthy. I've looked at Nexplanon a couple times, what's everyone's opinions on it? Did it work? Any side effects? Any issues? Please help, I'm so worried about all of it. This feels like a huge decision because I've never been on anything.