Am I overreacting?

I live in a household with 6 people and 6 animals. My brother, 22, is asked to do the yard work, and dishes and sometimes the laundry. My sister, 26, is asked to clean her level of the house, she lives in the basement with a bedroom, bathroom, and her sewing room. I am asked to clean the kitchen, dinning, living, and computer room and sweep, mop and vacuum the stairs to the upper floor and to the basement, and all of the other rooms mentioned. I am commonly expected to do laundry and help out with yard work and whenever my brother cooks dinner I have to do the dishes. I am only 14 and I understand that I have a lot less going on than my brother and sister, who are both attending online college courses and who both have jobs but I am still frustrated with the amount of work I have to do, not to mention if I don't do my housework first thing after I get home from school I get yelled at. Am I overreacting?