Toothache woes, any idea what is the cause?

So i wake up today feeling great and all of the sudden at lunch my front left tooth begins to hurt when I take a drink of Hi-C that is cold. Opening my mouth and taking a breath also hurts. The pain is not unbearable, more a nuisance. I have found eating foods, even peanuts do not aggravate it, but liquids that are not room temperature cause a pain. My mother suffers from sensitive teeth (not sure if its genetic). Really sweet foods have caused me problems before, but never cold/hot drinks until today. Can a single tooth become sensitive, or is it something more severe?