Dumbledore's strange words

Tweet

In HBP, we have the following language when Dumbledore and Harry return to the Tower. In the dim green glow from the Mark Harry saw Dumbledore clutching at his chest with his blackened hand. 'Go and wake Severus,' said Dumbledore faintly but clearly. Tell him what has happened and bring him to me. Do nothing else, speak to nobody else and do not remove your Cloak. I shall wait here.' Doesn’t this seem odd? DD sending Harry into unknown danger? A deathmark in the sky above and he sends Harry? Why not send his patronus?and then these strange words (in red):'That's right,' said Malfoy. 'But she said you were just going for a drink, you'd be back ...' 'Well, I certainly did have a drink ... ""and I came back ... after a fashion"",' mumbled Dumbledore. 'So you decided to spring a trap for me?' 'We decided to put the Dark Mark over the Tower and get you to hurry up here, to see who'd been killed,' said Malfoy. 'And it worked!' 'Well ..."" yes and no ""...' said Dumbledore. Any idea what DD meant by the phrases in within double quotes?And for purposes of the discussion, assume there was NO PLAN between Dumbledore and Snape as JKR has indicated in the Washington Post interview.