Severus knew Lily well enough to know that she was feeling self-conscious, it was just so hard for him to trust people. He always thought that she was his friend but being sorted in Gryffindor and Slytherin started to feel more and more like a strain on their friendship. His encounter with Remus the wolf at full moon and Black's hand in that 'prank' had hurt Severus' trust in Gryffindors even more. He hated being Potter and his mates' favorite victim.
"I am fine." He tried to make it sound like he was telling the truth but he wasn't perfect in hiding his feelings, he made a mental note to work on that some more. "How are you?" He had added that question before he had time to stop himself. He knew he was setting himself up for more hurt, quickly he glanced around afraid to see Potter and Black jump out.