To put it bluntly, he's so whiny and I'm losing the ability to deal with it. On average, I reckon he spends about 60-70% of the time when he's awake just whining at me.
Tiny little things will set him off. I changed the TV channel yesterday and he screamed at me. I sat on the sofa when he was at the other end of the room - he started wailing. If he gets hold of something he shouldn't have and I take it off him, he screams (but that's to be expected, I suppose). If I tell him no, he ignores me, then gets upset when I remove him from the situation.
When he's tired, he refuses to sleep but just wanders around whinging because he's so tired. If I try to cuddle him to sleep, he works himself up into a screaming fit. Oh, and he won't go in his cot without a fight either, and has to be either on the sofa or in bed with me. Which means I get no sleep because he's a massive fidget and usually ends up kicking me in the head. Frequently.
I think most of it is that he's frustrated because he can't communicate what he wants. But he makes no attempts at communication besides whining, and only babbles when he's happy. He wants to be picked up all the time, so I ask him "Do you want to come up?" as a sort of prompt, but he just clings to my legs and tries to climb me.
I'm at my wit's end, I really am. It's got to the point where I can't do basic housework unless DP is in the house (because DS prefers him to me!). If I try, I end up getting wound up by the constant moaning and leg-clinging and having to stop and deal with him just so I don't start screaming at him. 
What can I do? Or is this just a phase?