What snake is very small at birth and is very black and shiney?

it's small as a very small worm and it moves very fast. Very thin. Very shiny. Looks like a snake but so small you can't see with the naked eye the actual shape of the head? Is it a snake or can it possibly be a lizard of sort? It is night time now when I came across it on our porch. When I shined the flashlight on it it went crazy wriggling. We live in Tampa , Florida. The month is July 2011