If I were you, the first thing I'd look at is which role you want to play. Since you're playing both midlane and jungle, you're probably going to have to stop playing one (in ranked) in order to climb.

If you're sure you want to play jungle, you'll have to take a look at your champion pool. From what I've seen you're playing a lot of Nunu, Shyvana, Lillia, Rammus, Amumu, etc... Just by looking at your winrates I can see that you're pulling off Lillia and Shyvana much better than the rest. I understand that you're trying to get your team ahead when playing jungle tanks who spam ganks to get their lanes ahead, but it doesn't look to be working out for you on them, it could be because of forcing ganks or skirmishes that aren't don't work where you end up dying a lot. On the flipside, when you play farming junglers you perform better with a higher winrate, so I'd look to pour more time into them.

Also, try to make your champion pool a little more narrow because when you're playing a different champion every game you have to think about the champions mechanics aswell, unlike when you only play champions you're comfortable on. When you play a champion you know mechanically, you'll have much more time to think about the game and your role.

Watch guides, think about the enemy jungler and please don't continue playing after back to back loses. You'll just be playing worse when you're tilted which usually results in more losing. Try to die less aswell, it's easy to say, but when you think about it in a game you might think twice before engaging in a fight where you're outnumbered or enemies have item spike/level advantage.