I have had implanon for almost 6 months and have started gaining weight and feel pregnant could this be because of the implant?

Could be: Or could be from other causes , see your obgyn for an evaluation, i see a lot of side effects from implanon, i don't like them , and at your age if you are still fertile i would rec in office tubal essure, takes less than 5 minutes and then if u do not want periods after that i would offer u an in office endometrial ablation , so no more pregnancy and no more or very light periods.