At the garden gate

The wallet lay beneath a park bench, and finding an address inside made me glad that I could return it myself. An aimless afternoon had acquired a useful task. At the garden gate, however, I noticed the broken clasp and the empty space in the note compartment. I began to worry that something had disappeared before I found it. I could already imagine the owner examining me closely and mistaking my honest explanation for an excuse. Even so, leaving the wallet anonymously might appear more suspicious. I held it in plain view, prepared to give a simple account of where I had found it, and rang the bell.

In your own words, explain the writer's thoughts and feelings before ringing the doorbell.