Helpe-me

Hello, I need a very important help, I have 2 problems in my minecraft! 1 my player when I am running or walking, when I stop running or walking he keeps walking sometimes 3 to 4 steps or sometimes more !!! 2 problem my player mainly when I'm playing PvP my 'W' CATCH I can not but run only to get around to the sides and back but not forward and this is VERY creepy! And it's not a problem on my keyboard and I tested it and it works normally, and it's not setup in my minecraft !!! I do not know but what to do so much people help you, NEVER HAD IT WITH ME !!!! Hugs...