The feeling of being watched in Montgomery County, North Carolina

This happened around 2014 in the Thickety Creek community of Montgomery County, south of the county seat of Troy. A friend at church asked me if I could come down and check his creek for gold. He knew I liked to do some gold panning as a hobby. We never settled on a day or time, I just told him I would come by one day when I got a chance. I ended up getting off work early one day and decided to run down and wash some rocks. So, I parked at his gate and grabbed my backpack at gear and walked about 200 yards from the road. To my left is the creek with about 4ft banks and a steep mountain to my right. I walked down looking for a place to easily get down into the creek without lots of brush. This area is well known for huge Timber Rattlers. So I find a spot next to a huge flat rock that I end up using as a work station. After a couple hours of panning I stopped to take a break. I always freeze a 2 liter bottle of water and drink it as it melts. I’m standing there drinking the water and I hear something fly through the trees above my head. My first thought was “I’ve never heard a bird fly through the trees and hit limbs and leaves like that! Why is it doing that?” So as I stand there puzzled and confused I hear more commotion coming through the tree tops! This time my eyes focus on the sound and I see a rock about the size of a Jr sized football flying over my head and on the bank on the other side of the creek! As I stand there stunned, racking my brain try to make sense of it, I unsnap my 9mm and shout in that direction “You stay over there and I’ll stay over here!” Needless to say I packed up and left, feeling like I’m being watched the whole time! I threw my stuff in the back of my truck and hauled buggy out of there! I don’t know of any animal in the woods that can throw a rock that big that far! I was so effected that I gave up gold panning and hunting for the most part! I never told the land owner or anybody else for that matter for a few years. I still don’t tell many folks. I feel like I have to keep inside or people will think I’m crazy.