birth control
"I keep reading reviews about getting constant bleeding... I am the opposite. I started taking the 3 month deposit shots last year and got the nexplan on in December... no bleeding, no spotting, no periods! Lol its awesome! I will say I have increased pimples (but not on my face, hooray!) And lower sex drive. But it's not disappeared as some have described... me and my boyfriend still having fun :) 
Not sure if I'm gaining weight; and if so, I'm not sure if it's the birth control or my eating
I would say: TAKE THE SHOTS FIRST FOR 6 MONTHS. if you bleed on the shot you'll bleed on the nexplanon because they are the same hormone. With these sorts of things, always make sure the hormone works well with your body before making a 3 year commitment"