WIBTA if I didn't buy tissue?

Okay so I (20F) recently got a job in college to help me pay for my everyday nessesities and stuff because my mom (42F) would never help me pay for anything or put up a fight when I would ask for money to get things like groceries (I have a meal plan at my school but it is very limited so I have to eat at home to save meal swipes somedays). To note, no she doesn't even pay for my schooling my grandfather does because she claims she doesn't have enough to help me out when paying for school and we don't have a good relationship at all and do not talk to each other when I am back at school. So yesterday I came home so I could do my hair and the minute she sees me (no hi or hello, how are you doing?) she demands I buy tissue for the house, mind you I don't live here 10 months out of the year and I still need to buy myself groceries and toiletries, so I was caught off guard and just stared at her. Then she walked past me and said it better be here when I come home from work and just left. I was then told by my other mother that she had just spent 300 dollars to get the couch and carpet cleaned because she is hosting people over next weekend and she doesn't understand why she didn't buy tissue with that (also why she is hosting people when she claims she has no money) and I agreed so I didn't buy it because I didn't want to and I have things I have to pay for for myself because I get no help from anyone else (the tissue she wants me to get is the big pack for like 30 bucks). She then comes in my room early this morning asking why I didn't buy the tissue and going in on me about how I don't do what she ask me to do and I better get it today but I feel like I shouldn't have to. You payed money to get stuff clean just because you are having company when you can't even buy tissue for the house or groceries either (its basically a all man for himself household and my other mother is tired of always getting food when she doesnt contribute to anything). So WIBTA if I didn't buy the tissue? It seems that whenever she sees I do have some sort of money she's always asking me for some even though I really don't have it because I work a minimum wage job 2 times a week while she gets paid more than me and works everyday.