Biopsy

My boy Donner is going in for a biopsy on Monday. He has what appears to be either a discoloration or a lesion in his mouth. He goes in bright and early. That means no food no water after 10pm the night before. I am a bit worried about him. I try to look at the discoloration in his mouth, but he won't hold still long enough for me to examine him. I dont think that he is in any pain, because he eats just fine and runs around and plays like nothing is happening. Still, I worry. They are my children.