I haven't been chased by anyone while on my bike, but I once was followed while walking through a park, and I didn't even know it until a park ranger told me. A few years later, I was mugged in that same park, so crime does happen in parks, especially if you're alone and it's isolated.
You did the right thing by reporting the car, and by not trying to get a closer look later. Sounds creepy to me.
'02 Eddy Merckx Fuga, Selle An Atomica
'85 Eddy Merckx Professional, Selle An Atomica
'10 Soma Double Cross DC, Selle An Atomica
Slacker on wheels.