How much should I be getting paid?

Ok, so Im 20 years old, and Im not certified or anything, but I've been taking care of my grandmother for a few months now. I get my own small room and I share the bathroom and she has a computer that we both use with internet and she also had satellite tv before i got here, but she uses the tv a lot more than i do. I do about 80% of the cooking and/or meal prep, I do all the cleaning, and I even decluttered her house without her asking me to. I never ask her for anything other than my simple necessities. I also do about 98% of the driving because she falls asleep often and can't drive that long at all. I also take care of her two dogs and my own dog. I help her go grocery shopping and make sure she doesnt buy too many sweets, and she smokes, even though it is an even higher risk for her to smoke more than others. and she buys about $65 worth of cigarettes every month. I NEVER go out. And I just got hired at a job but it wont start for at least 3 weeks. So I have NO money of my own. I do a LOT of driving. We drive 45 minutes at least 3 times a week to go to her husband in the nursing home or to go to walmart, or a doctor appt. Which I am always happy to do. And we eat out at HER request at least 25% of the time. And I NEVER ask for anything I absolutely dont need. So even with all I do, including the last 2 weeks her sister has been visiting and i've also been taking care of her when she needed it. However, when I ask for simple needs like eye drops for my contacts, and underwear, she acts like I dont deserve it or I havent earned it. When I found out I needed medication, she acted like it wasn't neccesity, like it would be cheaper if I just suffered. And she is not completely helpless. If she had to, she could make dinner for herself and she can drive short distances, but we live wayyyyyyyyyyy out of town on a lake, so town is about a 15 minute drive. Which is almost too far for her so she can drive herself to church and the hairdresser. Thats it. And she is not at all mentally deteriorating. Shes smart and still does her crosswords, and can walk, but she is kind of large and has other multiple medical problems and she needs help with her mobility and cant do any heavy lifting or be on her feet for very long. She is NOT broke or poor in anyway. She can afford to get her nails and hair done at least once every 2 weeks and is getting the house redone. So with all this, I ask for simple things like cheap eye drops to keep my contacts from drying, and the cheapest walmart underwear I can find, and the cheapest body wash because HER body wash makes me break out really bad. And the other day I found a list of things she had bought me with its price, and added up on the back. This made me very upset, I'm nice to her and I do EVERYthing she asks me to. And it makes me really upset that she never even thanks me when I declutter and clean her very cluttered house. And as much as I want it, I never ask for ANYthing I want to eat unless she asks me if I want something. So I'm wondering, even though I get free furnished room and board, how much would a regular full-time caregiver get in my position? I do drive her cars and I'm on her car insurance, however, I NEVER go anywhere for my own need or pleasure. I dont have any friends at all here, I dont go to college and I have not been driving to any kind of job and the only time I drive by myself is for the rare job interview or to get a prescription filled. And it was her suggestion to put me on her car insurance as well. So if I weren't a relative and I was taking care of her with free room and board, but I did all of the above, with no other job, how much should I be paid? Because Im EXTREMELY pissed off that after all I've done, she complains when I need something for my health or if I need friggin UNDERWEAR. She does NOT give me any extra money at all and I never asked her for any before, but I need money for my own needs and she's being extremely hesitant and I'm completely helpless until I start that new job at the end of the month, and even then I obviously wouldnt be paid for another 2-3 weeks. So if she doesnt start buying me what I need, I'm gonna start giving her a bill with how much I should be getting paid. Because even though shes my grandmother shes being way too stingy when it comes to my very simple needs and I cant one day wake up and need soap, and she's too selfish about her own nails and cigarettes to buy me it. I use cheap products, and I simply ask for some help outside of just room and board and food. I appreciate all of it, but I have done everything she asks and this is very rude to me that she gives me a stank face when all I asked for was eye drops or underwear. Especially when she spends about $400 a year on cigarettes which make her have to have breathing treatments and oxygen and many other complications. Please tell me what I should do and how much a normal caregiver would get.