Password Stopped Working

I am trying to configure my home server from work. It has Windows Server 2012 R2, I'm using a permanent password for remote access. I have logged on and off several times without issue and been through several restarts. I just installed active directory and after the subsequent restart the password no longer works. I would like to know what happened, how can I keep it from happening again, and if it can be fixed remotely or do I have to wait until I get home?