I've never been to a dentist.. I'm almost 25...?

I've never been to a dentist because #1) My parents never had dental insurance and we couldn't afford it #2) I've never been able to afford my own dental insurance either. #3) I've heard SO many horror stories about dentists... I'm scared!! Anyway.. now I have no choice BUT to go to a dentist. I have had this horrible toothache now for about a month or a little longer. I don't know if it's just a cavity or what. It hurts to drink anything cold... it causes me to have a bad headache and toothache. It hurts to smile because the air hits it and triggers a toothache. It hurts to eat.. that also triggers a toothache. What should I expect? I'm really worried.. I don't want them to pull my tooth!! I hope I can just get a filling. Is it painful to get fillings? What does the procedure involve? Also, I'm really embarrassed to have to tell them I've never been to a dentist...
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Yep, it's a cavity! Chances are mate, you'll have to get a few fillings if you've never been! I've never had a filling needed at that stage - always earlier. The dentist will numb your gum and jaw, drill into the tooth until there's no decay, then fill it with a metal composite. Then they'll set it with a UV lamp. What may hurt a TINY bit is when your nerve is exposed. This is because they still bloody wash the tooth with water and it feels like probably what you're going through with cold water. It has to be ice cold to cool your tooth after drilling. Don't worry about it though!
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