Problems without flash, Nikon D80?

Lately when I've been shooting with my Nikon D80, even if I'm in a decently lit room if I'm not using flash the shutter speed is brutal. I'm in my bedroom right now, and it's morning so it's not dark in here by any means, and as I tried to take a picture of my cat beside me on my bed, even though my ISO is set to 1000 (my lens is 18-55mm), it still took about a second to take some of the pictures, and blur happened in almost all of them. I realize cats move a lot but even when he didn't the image just isn't been taken fast enough in general, and it's not as crisp as my photos used to be.

I never used to have this problem I don't think, my images used to be a lot sharper and crisper, and I usually had my ISO set from 100-400.

Thoughts? Is something wrong with the camera or what?

Assuming you haven't fitted a polarising or and filter, 3 things will determine the shutter speed: the amount of available light, the F stop and the ISO

If you have set the camera to the same F stop and ISO then the only thing can be that the room isn't a brightly lit as you think it is.

In a room with moderate sized window (no curtains) with sun shining but not directly into the room I would expect 1/50 sec or so at F/4 and ISO400.