Alistair looked agitated, he didn't travel such a long distance to be told by a measly guard that he had to wait. He made himself look more intimidating by slightly puffing out his chest and taking a bolder stance, he then spoke with a more stern voice to make sure his point got across to the guard.
"I don't think you understand, I'm here to marry the princess... not to wait on some hopeless suitors who think that they compare in any aspect to me."
Alistair wasn't about to move because a guard told him to, although many people sing praises of him being kind and thoughtful they all know that he is nore stubborn than a sunburnt mule. He made sure that the guard knew his place compared to a Knight of the People.