There was something weird going on between the boys, and I'm not sure what it was. Broken!Sam and panic!Dean is my guess. but the way Dean was saying, "Really? that's all you've got? 'Hello?'/'And me.'?" just... it was off. I didn't feel like Dean would have gotten het up about that in that way.

Yes, exactly.

think though that Dean's running towards what he needs from Sam, which is emotional presence, and Sam's running from that at the same time.

I think that's likely true, but at the same time, I don't think the ep did a very good job of showing us that, which is pretty unusual.