I'm learning that this is standard 2.5 yo behaviour. I believe a lot of what they do is to test you. With my DS I find some days are harder than others. Sleep & meals play big part, I find if DS is a bit overtired or its getting close to meal time he becomes very difficult to communicate/deal with. When he's well rested & full he is like a different boy!

Sorry I don't have any real advice, just sympathy because I know it can be extremely frustrating.