🆘 BIRTH CONTROL HELP!

So I'm going to the Gyno in a few days because I might be put on birth control for my period pains. They're the WORST... I've been doing my research on the best birth control and I saw the implant is the best one, but I also saw that it is really expensive... like $800, is this true? And if you're on it how does it feel for you? Like your symptoms, etc.