Swamped

Well, you don't need to tell the whole story. Still, you feel it's better not to try to bluff about everything.

"I'm a wizard," you explain. "I could sense magic in it. But I was a bit worried that I might not be in full control of my own magic right now, so I thought it was better not to get too close."

"Oh," the doctor says. "What do you mean, not in full control?"

"I was found unconscious, and I still don't entirely know what happened. I'm worried I might have had a spell go wrong. But it's going to be hard to be sure for a while."

The doctor glances down at the form.

"That sounds like it could potentially endanger the other patients," he mutters. "I should probably note that on your record."

"I'd prefer to keep it confidential. Even from hospital staff. It should only be a problem if I get near magical items..."

"And if someone brought an exploding clock here, we can't be sure they won't try to sneak in something else, can we?" he snaps back.

Well, you know that you never found out about the wizard in the hospital on your first day, so you've really got to convince him to keep quiet somehow.