Nice find and welcome to the forums, looks like a club that was tied on the end of a stick but i'm no expert lol someone will let you know. There is a sub forum for native american artifacts you could repost there for an I.D. Congrats!!
From my phone it doesnt appear to have been worked by man. Its just a "geofact" something naturally occurred that resembles an artifact
They are out there keep looking!
Your item shows no evidence of working by man. It is a regular old rock that was shaped by nature, but do not give up you are seeing shapes that are needed in finding those elusive arrowheads.