Should I be worried about a security breach if Google Maps incorrectly shows that I drove over 650 miles from home? I was shocked to discover that this past month Google Maps shows that I was home one day, drove from a neighboring location over 650 miles to Chicago the next day, and was home the following day.

Could this indicate that someone cloned my phone?

I know that inaccuracies can occur locally, but 650 miles? And Google Maps even shows the route that I allegedly took.

I searched for similar questions. Either they did not address this particular question or they were tagged as having already having been answered. If someone thinks that this question has already been answered, then please have the courtesy of providing a link in the comments.
In my case, the solution was to turn off location services on my Android tablet. Google Maps was using my ISP to guess my location.

Although I was in Alabama, my ISP was reporting my location as Chicago, so Google Maps assumed that since I was in Alabama one day (according to my cell) and in Chicago the next (according to my Android tablet), then I must have driven to Chicago (even though my cell was still in Alabama). Then it produced a likely route that I would have taken. Note that I seldom use my Android tablet and that the Chicago thing occurred when I first turned it on after changing ISPs.

This is the best explanation I can come up with.

So if your location service comes from your ISP rather than your cell provider, make sure that your ISP gives an accurate location for you.