Screaming or howling in Lorain County, Ohio

I was 17 years old and was out deer hunting with my bow and arrow. It was just starting to get dark out when I heard something moving about 200 yds. away in the pinetrees. A couple minutes later I heard 3 deep grunts. At first I thought it was maybe a big buck Grunting for a doe but the more it kept grunting the more I thought it was maybe a rapid dog. It was making alot of noise as it came closer to the opening to cross to the other side of the pinetrees. It stopped just a few feet from the opening to the path. It just didn't feel right so I didn't even draw my bow. I remember grabbing my knife for protection (I was in a tree stand but kept thinking the "rapid dog" would bay me in the tree!). After what seemed like forever I heard the most blood curdling scream as it jumped acrossed the open path and into the other pinetrees. All I remember was saying to myself "oh my God it was on 2 legs." It took only 3 jumps to cross 20 feet.It was starting to get dark and was about 50 feet from me, so I couldn't tell the color or features. All I remember was that it was big and only on 2 legs. It kept screaming (like a bobcat scream or a little child's scream) and was running so fast into a big wooded area. I jumped from the tree and ran back to my house with tears in my eyes. My parents weren't home so I ran to our neighbors house and called him to his back porch. He heard the screaming and the animal breaking wood in the woods. He told me he has never heard anything like that ever. My parents ended up not believing me.