I didn't even know that could happen

That's a phenomenon known as image persistence. It's not generally harmful or permanent, but it shouldn't be happening unless you leave the same image displaying for an extended period of time. If its happening fairly quickly then there could be an issue with the driver circuitry for the display.

If the display is still under warranty (seems unlikely if it's a 2011) then you could try to contact Wacom for support, but failing that it's probably time to start saving up for a replacement. (Don't forget to look at competing brands like Huion, Monoprice and the like)

Oh wow, I have never heard of this; thanks for the info--I was going to comment myself saying that it happens sometimes at work, but isn't persistent... I just got a cintiq myself recently so I will keep that in mind, since mine I bought used.

I also heard a lot of people using a Yoga (I forgot the full name, but it is a tablet)~ Great reviews from friends about this!

Well dang. Would it matter if the tablet is off, and I have the image is open? (Unlikely but I kind of figured I'd ask anyway?) I was told after I bought the tablet to never leave it on if I was not actually drawing - which I never have. So I'm usually extremely paranoid about leaving it on while I don't have my pen on it.

I guess I will have to put money away, thanks a ton for letting me know. And I'll check out the other brands for sure.

There's only three things you need to worry about with LCD monitors (Cintiq or otherwise) as far as leaving it on.

1: Image Persistence, which usually only happens after a number of hours with a static image, and might need a few hours of displaying a white screen to clear out.
2: Backlight lifetime, which is more of an issue with CCFL backlights than LED. They usually last a good 5-10 years, but will dim over time.
3: Power supply components, such as capacitors. There was a widespread issue a few years ago where some counterfeit electrolyte got into the global supply chain and caused capacitors to dry out and fail after only a few years, but even a quality capacitor can start to fail in 5-10 years if the circuit isn't suitably engineered.

As far as image persistence I'm actually only seeing this in photoshop (since it has the really dark background, and the image I'm working on is mostly white) and not Sai when I do the same thing. Yesterday/last night it wasn't doing it on the same image in PS so I'm really curious what could have changed over night. If you may have any insight, I'm just picking your brain at this point.

Well that seems a bit odd. Do you have your Cintiq mirrored with another regular display? Does the issue show there too?

Mirrored? Uhh, I just have a regular monitor other than my Cintiq (It's an acer), and no it has no signs of doing the same thing. I'm just going to stay away from using bright colors in photoshop and stick to Sai for those to hopefully not agitate it (if that helps at all). It just seems super strange to me.

Mirroring is what it's called when two monitors show the same image/windows/whatever, as opposed to adding more space where you can put different windows showing different things.

oh wow, never had that problem with my 21UX but seems like you got it pretty well and figured out now.