Oh SURE!
As long as the finds keep coming, everything is hunky dory. But, let them slip, just a bit, on a site where expectations were high and right away, Gee I hope the machine ain't broke.

LOL
It sounds like you have what I call a "clean" site. Believe it or not. Not EVERY household trashed their yards. Some people actually take the time to find and use their trashcans.

They can be a very pleasurable place to hunt. Maybe, sometimes, a little boring but still nicer than a trash hole.
If you doubt your machine, dig a hole and bury a quarter. It might tell ya something about the ground anyway.
I'd say you have a fine start. Listen really, really closely. Might be a deep ground!
HH!