When Miss Thomas asks about the bites what does Bud almost tell her?

Bud initially decides to tell her they're vampire bites, but then he thinks it best that he tell her the truth.

For a second I was going to tell her they were vampire bites, but something told me to tell the truth this time. I said, "That's just some hornet stings, ma'am, I got bit up when the Amoses locked me in their shed."