Visiting family over holidays

I am visiting my sister currently for xmas, and my parents left yesterday and they were sort of the “buffer”. because while they were here i was able to stay in the room and sort of keep to myself. I’ve never been close to my sister and the main reason im still here is because there were no flights back to my country till the 5th. So now i feel obligated to stay out of the room and awkwardly interact with her husband who i don’t know that well and have awkward conversations with her and him, not to mention they’re religious and i am so so far from the way they think and act. and in my family and culture it’s expected that the guest cooks and cleans for the host as a sort of “act of kindness” for them and if it’s not done we are seen as rude or disrespectful and ungrateful. so now i feel extreme pressure to cook and clean for them. My sister even said today “you need to cook lunch since you’re not doing anything and we have to go to work” which is fair enough. But if i touch any of her appliances they say comments about not breaking them, like i used the coffee machine wrong and it leaked and they got so angry at me and i can’t cook at all, so i cried in the shower because my brother in law tells his parents everything (they live next door) and it feels like i can’t breathe due to humiliation. If i clean it’s not done well enough. I feel like im walking on eggshells everywhere and i just stay on my phone when in common spaces because staying in the room they see as rude. one week to go and i don’t know if i can do it. Im currently sat by the table and theyre on the sofa.
Not to mention I am also always hungry because they eat really small portions (my sister is very petite and skinny) and im too anxious to ask for more food my stomach hurts from hunger like acid, i cried in my room last night because im so uncomfortable and anxious. Like she’s my sister and i wish we were closer but the age gap is 10 years and she moved out of home when i was 8 years of old to a different country and we only saw or spoke to eachother a couple times a year. Sorry just had to let this out to someone i am literally trapped because there are no flights till new year.