If someone gains access your account and has done something, You are responsible for your account, and will face all blocks and consequences, unless we can prove your account was compromised using CheckUser.
Tips on keeping your account secure
Have numbers and letters in your password.
Make your password long.
Do not make your username your password.
Do not ever give away your password, not even to an administrator.
Change your password every few weeks.
Make sure your password is too hard for someone to guess, but easy for you to remember.
Do not make your password have to do about something everyone knows about you.