For whatever reason, the film was either grossly underexposed or grossly underdeveloped, or maybe a combination of both.

Your example has the classic look of underexposed/underdeveloped film that the printer compensated exposure on to try and get something usable out of it. Anytime you see that green tint and low contrast combined, it's a sure sign a negative with not enough density is being printed by underexposing the photo paper to compensate.

The possibilities:

• Your camera underexposed the image by either closing down the aperture more than it was set, or exposing for shorter duration than set. Usually, when a camera misses a setting it's in the other direction: Either the aperture is left too wide or the shutter is left open too long.
• Your camera's meter is out of calibration and recommended an incorrect exposure value for the lighting conditions. Your stated settings of 1/125 at f/8 for 400 speed film is approximately Ev10011, which is appropriate for deep shade during midday or unshaded areas right around sunrise/sunset.
• The developer used to develop the negative(s) was weak or the film was not allowed to remain in the developer long enough.
• The film was out of date or had been stored in poor conditions (primarily in high temperatures) and was rendered far less sensitive than box speed by the time you used it.