MacBook Pro Mid-2012 13 inch disfunction of keyboard and trackpad

Question

This evening, seemingly out of nowhere, my trackpad, and then my keyboard, progressively seemed to degenerate into a state of semi-unresponsiveness. Simply put; none of the keys on my computer will work. I tried bringing everything back to default. The trackpad isn't working properly. I cannot single-click on items; when I tap, the computer interprets it as a double-click. Some simple swiping motions still work, like the three-finger swipe between alternating desktops and the dashboard; however, on the whole, my computer is basically disfunctional. I can, with great difficulty, open up a program, but navigating it is next to impossible. Some basic software functions also seem to be deteriorating; I cannot click the "back" button at system preferences. I cannot click the help icon, and i cannot fill the cursor in a help space. It is terribly frustrating. Finals are coming up. I have a lot of important stuff saved to my computer.
I can access my guest account on my computer, but due to the fact that the keyboard isn't working, I cannot type in my password, and therefore I cannot access any of my personal files or anything on my account. I'm dying here. I don't know what's going on. Please, if there's anybody out there that can help me...
This seems like a software problem. I'm hoping I didn't get a virus (I understand that's pretty rare on Mac; I do not recall clicking on any suspicious material any time recently. My computer was functioning perfectly fine just before the incident began. I do not recall doing anything that could have made this happen. It just happened out of nowhere.
     I read somewhere that it could be a wire/ribbon next to the battery that could have overheated and slightly melted, impairing the function of the trackpad and keyboard. I do not know whether this is likely.
     It appears that, upon first turning my computer on, it will allow me to type a few letters right away, such as A, S, and D. However, when i try to continue, it will not. I then have great difficulty trying to delete it, and yea....
     I plugged in my USB mouse, and it does not seem to be faring any better than my trackpad.
     Please help.

Answer 1

Thank you very much, sig. I can't figure out how to indicate that your response sovled my problem. Yeah, it turns out that there wasn't really a way for me to personally fix the isssue with my computer. I took it in to the Apple Store, they checked it out, and told me that they had to replace the entire keyboard/plate, and the warranty totally covered the costs. Everything is back to normal. Life is good.