Can't access Terminal or admin account

[griddigus]

I have a complicated issue, please bear with me! I seem to have really screwed myself over. My 2011 MacBook Pro (Maverick) won't let me access Terminal. Once or twice it showed up for a second but then went immediately back into the Safari-only guest account or login page.
Im trying to get into it so I can reset the admin password, because after doing a PRAM zap, my usual password doesn't work &/$;!-#€!! It reset the password on me I guess?? And I know it's not a keyboard screwup, I tested for that.

I also tried Internet recovery to reset the pw but it just got stuck. I don't think I have a Recovery partition.

I even tried booting up from an older install disk I had lying around but it wouldn't boot from that either.

It just seems like I can't use anything but the stupid guest account. And even in that now it shuts itself off! Hardware Test said everything is fine.

A Yosemite update appeared in Installer just before all this happened but I didn't update it could that have something to do with it?

Can anyone pleeeease help me out of this nightmare? I would be most grateful!

 

[Cory Cooper]

Hello and welcome.

Sorry we didn't get back to you sooner.

-Does you account still show in System Preferences... > Users & Groups
-You're not using root as your daily account, correct?

Here is a step-by-step guide on how to reset passwords using the Recovery Partition and Terminal:

OS X Mavericks: How to Easily Reset the Administrator Password

This will work for Yosemite as well. Bar in mind that you may have problems with your login Keychain if you can't remember the original password. We can help you delete it and create a new one of that is the case.

C