It does sound a little hard to believe, but I had couple similar incidents happen when I was in college. Once I was just strolling around campus after a night class because I had like 20 minutes to kill before my bus would come. Another time a friend was gonna give me a ride home, and the plan was to meet in the parking lot (in retrospect, a bad plan because the lot is huge) so I'm walking around trying to find him or his car with no luck for several minutes. Both times campus police decided totally innocent behavior was suspicious and hassled me, quite a bit in the second case. Security cameras also featured in that incident.