I'm sorry. Whatever happened don't let your sorrow just build and build inside you. Join a specific group, honor him in different ways. There are support groups for losses of many kinds in towns and online. Here too I'm sure.
Sorry for your loss, can you give us a bit more detail. Was he a baby or older child? Not that it hurts any less...but maybe with more info a mom out there would have something in common with your situation and could help you through such a terrible time.