I was getting bored working on my site so i decided to log out (switch users). When i got back and tried to log in it wouldn't accept my password so i tried to log into the unprotected admin account... and it had a password. I restarted my computer and turned off my router (paranoid) while it finished turning off. When it got to the log in screen everything went well and here i am. I'm asking wtf happened (lol) because I'm not sure if this is a Windows bug or a malware/hacker problem. Any feedback/help is good.

Thanks