Messed up colors

I checked the memories, but I wasn't really sure where or what to look for, so sorry if this is in there.

My colors all of a sudden messed up in photoshop. One second its all the normal colors with three bars, and the next its got only one bar with just gray/white/black. Whats even wierder is that it doesn't actually color with those colors, it darkens or brightens and I have no clue how to fix it. Maybe its because the image I'm using is already black and white because on other pictures, it was normal colors :/

Here is a pic of what the color looks like and the picture I'm using
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ad here is where I used it, its easy to see where it was darkened/brightened in the pic.
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any help is appreciated ^_^