Be afraid of the darkness.
If your monitor has not been calibrated properly within the past week then odds are that the colors you are seeing on your screen are NOT representative of the actual color values from which they derive.
Monitors tend to skew brighter as the calibration gets off. So on an uncalibrated monitor the actual color values are most likely DARKER than the colors you are seeing on screen. In some cases they could be SUBSTANTIALLY darker than you realize. You might think you have a nice peachy flesh tone, when what you really have is a burnt orange.