Lazy and not sure how to make him move

Well, tonight was another frustrating night. I had cooked dinner after running and getting 11 kids from school and picking him up after he got off work. I had done all of the dishes and worked on some homework on my day off. As my son was being scolded for not behaving at school and I was trying to get him to work on a paper stating the rules, my youngest kept kicking the wall in her room. I yelled a couple of times and she was not stopping. At this time he was sitting on the couch playing on his computer. I hollered for him to see if he could get the youngest to stop and all he did was yell to stop. If that worked she would have stopped after the three times I had yelled. So in a loud voice I said it might help if you get up off your lazy ass. He gruffed at this but then eventually went to her room to stop her. I am just not sure how to get him to understand the stress he leaves on my shoulders. He then says to me at 9pm that he is going to bed and asks if I have much homework to do. I just laugh and he says goodnight. Is this really all the support I get? Should I make a drastic comment to make him aware of what is happening? I am very frustrated at work and this at home does not help at all. The only good news I have received this week is that my son got approved for the gifted program and he gets an IEP. Yeah finally someone is listening.