I started playing ranked and i am awful

Hello, I am level 30 for 2 months, and i have 70% win rate in normals and yesterday i started playing ranked. AND I DID AWFUL. I am in losing streak for 15 days without any win in normal or ranked, but i was so excited about solo q and i started to play. All of loses are my mistakes. It's not end of world cuz i lost only 2 matches, but it feels like i am placed in Paper VI. Lets have a quick description of first two games: Game 1: I got mid and picked annie. In enemy team there was xerath that bullied me in lane so hard that i couldnt even farm, and their lee sin camped me. Ended with 3/11 kd and 90 cs. Awful. Game 2: I got jg that i didnt want to play, only jg i have is khazix. My brother that is 7 started pressing random buttons on keyboard and took off my headset. I raged extremely hard and their lee killed me 3 times. On mid troll syndra fed their veigar by giving him 9 kills in 20 min. He killed me 7 times. Terrible. I dont see where is my problem. I ward always when i have a ward and try to afk farm until 20th min. I never flame or leave. What can i do to get out of losing streak? PS: i went to op gg and another elo prediction website both told me i will get B3, that is not to bad xD but it feels awful to feed in ranked