I pulled out of the parking space at the office and made a couple turns in the parking lot. Then I started to hear a clanking noise that sounded like it was comin' from the passenger side front wheel. It stopped when I came to a stop sign. Then started up again briefly as I left the sign. It stopped pretty much right after I left. When I got to my house for lunch, I checked the lug bolts to see if they were all still there, and they were. When I got back to work, I walked over to the stop sign and all I saw was a piece of mulch in the road. I didn't notice any change in handling or anything while driving, and I even got it up to a decent speed on the interstate. Is it possible that as I was drivin' in the parking lot I picked up a piece of mulch in the wheel and it was just floppin' around in there as I drove, or should I be concerned that nut or bolt fell off somethin'?