When my ds say he can't be bothered or 'i'm not going to do that' I simpy say ok, I won't bother cooking your dinner tonight then, or I won't be taking you to [activity/friend] you wanted. He usually does it then.
We also have one computer and it is mine. So if he wants on it he has to let me finish in peace and needs to be dressed, have breakfast and brush teeth and hair before. Hoever he always asks when he's not, and I always say not until. He then rushes off to do.
I don't always give it to him right away as I have to use it and do have to explain every so often it is a work tool, not just a game tool and he needs to wait.
But I do usually give it up fairly soon afterwards so he's not waiting for ages wondering why he bothered.
I do sometimes get fed up when I have stuff that needs doing and he's playing games on there. But I also have chores that need doing so I go off and do those for an hour and then it's my turn again.
Have you put a password on your screenlock for the computer? Same with tv if it has one. Or simply hide the remote or remove batteries if he automatically switches it on.
My ds has always had to ask for tv to be on and it's rarely allowed before 8am.
And he has always to ask for everything, tv, wii, computer. Because I have always dine this he never switches things on without asking first. We have a small house and using this stuff effects everyone in it. You'd have more trouble enforcing that now if you've never doen before though.
Recently I have been restricting the computer time as he'd be on all day given the chance. So I say ok you can go on for another an hour this afternoon but only once we've been out for a walk without fussing about it. He doesn't like it but that's how it is. Bad behaviour is dealt with by removing a privelage. And tv, wii, computer ARE privelages not a right as he sometimes seems to believe. So if he moans about going for the walk then I simply say 'any more and you'll be losing 5 minutes off your time'. Doesn't always work in stopping him, but he now realises I mean it and is more likely to listen after the first warning.
It's tough especially when you try and install new rules or change how things have got to. He will fight and push you very hard to get them dropped and back how he wants it. But you mustn't give in as he will know that he simply has to up his game next time and you'll give in eventually...
Like when I tell ds his time is up on the computer after giving him 10 and 5 minute warnings and i get 'but I just need to finish this level'. I say it's his choice but he's using up his afternoon time now and 5 minutes extra counts as 10 minutes off afternoon. He pushed this, but after he lost a whole weekend as a result he tends to rapidly finish but it does give him some choice and the chance to finish off.
Actually I quite enjoyed that weekend without the computer. He moaned and complained and went to his room to sulk and came back a while later with his battleships game asking if I'd play that with him. Can't remember when we last did that!
I suggest you sit down and have a frank talk with your ds. Talk about the things that upset you and make you shout. Ask him what upsets him and makes him shout. Tell him what new rules you'd like to introduce which will help stop you shouting, and ask him what rules he'd like to see which would stop him shouting too. Be neutal, unblaming, but honest. Explain you are tired and stressed and that you have to do your coursework, just like he has to do his homework. I did this a couple of years ago and it did help us.
Agree on a plan of action and some rules (you have final say on these if he comes up with something thats not going to happen but make it a give and take thing where possible). My ds said he wanted me to shout less, I said I wanted to shout less so he needed to listen and do what he was asked and keep his room tidy and get his own lunch if I was working. He understood this more when I explained it.
So write up your rules so you both know what they are. Rules for both of you. Ours included less shouting, more listening, more family activities together which we take turn in choosing. And write on there too that computer etc are a privelage and are not to be automatically expected.
Apologise if you shout and swear again, explain why it happen (you nagged me for breakfast while I was trying to do college work and I asked you to wait or get your own and you didn't - so he can see cause and effect) and explain as per your rules that he will now get his own breakfast which will mean you can do your work and the shouting will not occur as a result.
Things may get worse before they get better, but he needs to see you mean business. If you give in or say that you can't handle him because you're not a 'man' then you're simply giving him free reign to walk all over you.
He doesn't get away with that at school, why should he do it at home.