What is wrong with my nikon f-301/n2000?

When I shoot in aperture mode and I make the aperture wider (smaller number) it tells me that the photo is going to be underexposed and if I make the aperture smaller (larger number) it tells me that my photo is going to be overexposed. Is there something wrong with my camera or am I just doing something incorrectly?

Could be the meter is faulty. Could be you are reading it wrong.

P-S-A-M, Program mode-Shutter priority-Aperture priority-Manual mode. + is overexposed, - is underexposed. If everything is right, your camera is wrong.

Is the lens locked at the stop down position? If you are changing the aperture and the lens isn't actually coupled for camera aperture control then the meter will have no reference, you need to check the tab on the lens and recouple.