AITAH for refusing to help my sis in her English exam?

So i (21F) and my sis (20F) share the same room, we've been roommates since forever, even tho we don't really get along, i'm more quiet and she's loud I respect her as a person I don't talk/study loudly while she's asleep, sometimes i go to a different room so she can get to sleep, she does the exact opposite when i'm asleep she gets louder, turns on all the damn lights leave the door open, all sorts of annoying stuff. Sometimes i get overstimulated and I don't wanna talk or hear anybody talk, i just wanna be left alone, she doesn't understand that and still talks to me and annoys me anyway despite telling her to STFU. We kinda had a major fallout, we're not talking to each other, and if we do we'd yell. It's finals season i had to move to the guest's room so i can have some peace of mind,I only got my mattress and my desk i never went back to our room. Today when i got back from college my mom said "ur sis has an online English exam, i think u should help her" i was like idk I can't take what she's done lightly since it's not the first time doing that and i was gonna say okay i'll put everything behind me and just do the exam for her, till she showed up outta nowhere and started yelling at me for no reason at all, i was like that's it, idc if she fails it's none of my concern anymore. I went on with my day in the guest's room, and then my father texted me (he's outta town), he was like" ur sister needs ur help her future is on the line, and now ur true colors are shown, u should put it behind ur back and just do it" i was like " this is her own fault, i beared her for long enough and now she's treating me with disrespect, she needs to take responsibility for her actions" and she knows she's wrong that's why she never came up to me and asked for my help, she sent mom and dad as if it's gonna make it alright. For me i can take whatever and I'd handle everything until it comes to my own self, I haven't given myself the value it deserved back then but now I'm setting boundaries and it bothers them. I think my parents would think that I don't value or respect them since i said no, but i also think they know it's not abt them (hopefully). So u yea AITAH for putting me first? TL;DR me and my sister had a major fallout, and my parents are pressuring me to forget abt it and answer her online exam.