Yes. Some of this is about being a teen, but that doesn’t mean that your feelings aren’t valid. You are at an age where you are asserting some boundaries between you and your parents. You want more privacy. You want to have more say in many things. It’s normal to want to put a little distance between you and your folks.
There are two problems here as I see it. You think the room is YOUR room. Your mother thinks that the room in in HER house so she felt she had a right to be in it. She was probably “picking up after you” just as she did when you were little. That’s help that you no longer find helpful.
The other problem is that you are getting furious and fighting about it instead of communicating. That (plus keeping stuff on the floor, etc.) makes you look immature and reinforces your mom’s idea that you are too young to make decisions about privacy and how to keep your room.
There are also two ways to solve the problem:
First, start to keep an orderly room so that your mom doesn’t have reason to be in there.
Secondly, have a mature talk with your parents about your need at this point in your life to have some privacy. Reassure them that you aren’t doing anything you shouldn’t; that you just want to be treated more like an adult. Don’t yell. Don’t blame or accuse or make excuses — even if either of your parents do. Just calmly restate that you want to be given the chance to show that you are growing up and part of that is keeping your room reasonably picked up without “help”. It’s certainly okay to point out (calmly) that your room is the only smoke free part of the house and to ask (not demand) that they allow you the courtesy of keeping it that way. It will take some time but the more you act like an adult, the more your folks will probably treat you like one.
I wish you well.