logging into servers

hello mojang! i know you probably have alot of these bus issues from people, but everytime i try to log into a server, it sais failed to login: try retsarting your game... i reallywant to play with people, but only 3 servers work. one is ALWAYS full, the other two ask me to sign up when i already have. when i try to register, it sais wrong password, or passwords do not match. it also sais i maxed the amount of registers or something. i have only registered to those 2 servers once or twice. please help!