I played my placement matches right after the sever wiped when it was really laggy and people were dropping from 4v4s constantly. Somehow after I finished all five though I got put into platinum and i've been getting owned quite often ever since, is there anyway to drop down a league voluntary? Lol
The same exact thing happened to me - there's no way to voluntarily demote yourself, but it'll happen soon enough. It seems like the placement system is a bit wonky. Meanwhile you can at least learn from playing with good players.
Keep playing! The more you play, the better you will get, trust me. As long as you don't do the exact same thing every single game. Also, try to watch some replays of top players of the race that you play.
"Listen up, Simon. Don't believe in yourself. Believe in me! Believe in me, who believes in you!" EDIT: my bad my bad...this is what you should do: "Listen up Simon and don't forget: Believe in you, not in the me who believes in you; not in the you that believes in me. You should believe... believe in yourself!"
A lot of good players are below where they should be because of drops and lag. Give it time and they'll get back up to where they should be. Until these problems, I was always where I should be. Now, I can sometimes play someone a lot better than me who has the same score as me. By the way, scores are infinitely more important than rank.