Did the snake seem to have a faint ring around its neck?
Did it look like this?
Does this look more like it?
The snake on the top is a ring neck. They are black, with a yellow or orange underside and are as you decribed as worm like. THey may or may not have a rung around the neck.
The second snake I posted is a worm snake. It too goes from shiny black to grey in color and yellow underneath. Both are usually found burried under items. If neither of these match, please let me know and I will see if there is another snake that may match the description that lives in the area. Joan
THis is another wormsnake picture: