Im very new to implanon, I have been on birth control pills for about four years, and I just decided that implanon might be a good choice for me because I am not good at keeping tabs on taking the pills. I have not had any change in mood swings, appetite, weight gain or loss, headaches, or any of that. Only issue I seem to have which is getting annoying is my period. After a week of the implantation, I started a very light period. Every day for the last three weeks it's light, but I don't know when I should see my doctor. When do I know if it's been too long? How long should I wait?