Implanon

I've had the implanon for the past 3 years and it expires in a few days. I'm thinking of getting the copper IUD however I don't want to lose my sex drive ( it happened with the implanon) and I do not want to gain any weight and most certainly do not want to get pregnant again? 
Any advise? What do you suggest ? Please give me any information you have. Anything helps at this point 
Thank you! :)