Tooth ache. Front tooth?!

My front bottom left tooth is in unbearable pain. Of course I'm booked into the dentists very soon but I've been with this before and they said 'its just sensitive, have some sensitive toothpaste' a month later a bit o the tooth fell off, I went back and had metal fillings. Even I can see that my tooth is worn down.
It's so painful!
Any tips on how to ease the pain, what I should say to the dentist etc. Xx