Five million Gmail (and therefore Google Account!) passwords were stolen and posted online yesterday.
Use the site haveibeenpwned.com to check your passwords against this and other major breeches.
This is a great time to update your password and enable two-factor authentication.
Also, if you don’t already do it, start using a password management system. I like using Keepass with DropBox (aff. link), but the most important thing is to start using long (like more than 17 characters!) passwords.