I was already logged in. I'm generally the only one on this computer so I have it set to remember me. The last time I was logged out was 3 or 4 months ago when my sister borrowed my computer
You could try filing a password reset ticket (keeping in mind that, being the weekend, it may be a few days till you hear back) and just explaining the situation.
Check your emails to see if the password is still in there somewhere.
Save your password somewhere secure so that if you do forget again you won't have a repeat of now.
Depending on your browser, you may be able to retrieve it through there. Since I don't use saved passwords, I can't remember how to do it, but I believe you should be able to look up saved passwords somehow. I'd google it and see if anything comes up for your browser, as it should keep it somewhere for you.
If you have more then one browser, see if you're logged in on the other browser. Maybe you can do the normal 'forgotten password' thing on another browser that you're not logged into?