Depends totally on the size and shape of your room... you could probably fit it but it might get in the way, then again if you're a musician you will miss it alot! I suppose its about a balance.
As for the whole 'should I ' thing, I don't see anything wrong with it. If you were going to play it really loud, at night time, or disregard people asking you to quiet down then yes it would be wrong. But I can't imagine you'd do any of those things.
I can only speak for my own uni but they wouldn't mind an instrument at all, unless other flatmates complain about it, which if you're good with it, they should have no need to. They only generally care about keeping everyone happy.