How to Stop Chewing Your Lips and Cheeks?

I just started getting lots of teeth pain from biting the my lips, insides of my mouth, skin on fingers, nails. It was so bad I just had to only think about it through the pain. I let myself focus on keeping my tongue on the roof of my mouth instead. Eventually the pain will subside through not using your teeth to bite things that are really just making your teeth grind on eachother. My front teeth have chips and I wore them down to the point where I can't use them to bite things or else I'll get pain. I have to prioritize using my back teeth. Dentists don't understand because I'm not officially diagnosed yet. I think.. would they ignore a autistic person coming in for dental work due to biting stims. Idk I haven't heard someones experience yet. Hoping to. I hope you aren't as bad as me, this is honestly the worst thing to have when you're a healthy young person. Makes you feel like you're already dead cause life sucks with constant pain.