snakes are usually a sign of sexual energy, the kundalini in hinduism is represented as a snake coiled at the base of your spine that springs up in times of great emotional or sexual awakenings.
Perhaps you have some sexual feelings that you're not ready to deal with, as your son and mom had no fear of the creature(son to young to worry about it, mother done worrying about it.) so like your son showed you, chill out, smoke a cigarette and let the feelings recede and address them, you can't escape what you're feeling, just sort them out and deal with it.