My Nikon D3100 Takes greyish pictures?

I never had this problem up until a month ago. Whe I used to take pictures in my room, I would always use the same settings and it was always fine. Now, I use the same settings and the pictures are all dark and greyish now. Even if ai put it on rhe lowest settings it's still greyish. But if on Auto it's completely fine. What happened?

It works in Auto, but not in some other mode. Must be the settings in the other mode. Either open the aperture or use a longer shutter speed or a higher ISO.

Sounds like pilot error to me.

I would have to have your camera in my hands to tell you what's going on, but try changing the white balance and/or color modes (vivid, portrait etc.) and see if that does anything…