Inplanon inplant

So I've struggled with very very bad, heavy&painful periods from the age of 10 (I'm 19 next week) I had an internal scan before Christmas and it showed a cyst on my ovaries, so I thought that was the reason my periods were ridiculously bad, then I went back for another internal scan after Christmas&the cyst had gone. But nothing's changed! My periods are still ridiculously painful, heavy&just horrible! I asked my doctor if he can put me on a different pill (i take 2 pills called norenthiscope every day at the moment but they don't help at all) the doctor said he can't change my pill because of my weight but he suggested I have this inplant called inplanon aswell as taking my pill, I've read up about it but I'm quite scared to be honest, I've heard they can go wrong&it really hurts when they put it in, I dunno like I really want it done cos I can't go on like this with my periods cos it's just ridiculously painful but then I'm also really scared to have it done😰 my boyfriend said he'll come with me and hold my hand but I think the thought of having something the size of a match stick in my arm is off putting& plus my pain threshold is very low&I'm petrified of needles, could someone reassure me&maybe tell me more about the inplant please? As even though I've looked it up I still feel like I don't have a clue haha