AirTag Found Moving with You

I received a notification that an AirTag was found moving with me, two separate AirTags, around the same time. The first was seen at around 4:30 in the morning and disappeared at 1 in the afternoon. The second one was seen at also 4:30 in the morning and likewise disappeared at 1 in the afternoon, but had a different pattern of movement. I got the notification on my iPad but not on my iPhone. Looking at the map the AirTag seem to have moved erratically around the vicinity of my parking garage, and my iPad was covered up in the backseat of my car parked all night. My iPhone was with me of course and didn’t get a notification. Any explanation for this? Is it possible that there was an AirTag on someone’s person or another object simply in the vicinity of my iPad and it picked it up overnight? Thanks!