Evil Dog

My pretty chill run turned into a run from hell! I was running up this hill about 7 blocks from my house when i looked up & saw this boxer/pit bull-mix (meanest looking dog ever). I am not scared of dogs but when i saw this one break away from his metal chain that was keeping him tied up. I stopped dead in my tracks about 50 meters away from this dog & just stared at him. He just stood there growling & stared straight back at me. I had a feeling that i needed to turn around & get out of there as quick as i could so i begin to walk down the hill & get away from him. Before i knew it this dog began to chase after m. I had no where to go! To my right was a house with a small front lawn nothing else, to my left was a big open field, a few trees & a bob-wire fence surrounding the field. I, being scared to death, walked briskly to the nearest tree & wrapped my arms around it as i whipped out my phone & pressed the speed dial to call my house & then i began to pray that someone would answer & that this dog would not attack me. Within 2 seconds this dog was not even 5 inches away from me growling & barking. He began banging into my leg with his mouth/head over & over again. I felt wet on my leg & thought to myself, i'm gonna get bit! Each time he hit into my leg harder & harder, my heart stopped because i was sure he was gonna bite me. I didn't dare jump over the fence into the field because i knew he would follow right behind me & probably attack me, so i just stood next to this tree trying to fight back the tears. Luckily after a few rings my mom answered, i was only able to spit out, "Come get me, i'm at 180W & 1300S" My mom heard the terror in my voice & then heard the growling. Within 30 seconds my sisters pulled up in their car & the dog took off running. I'm sure if they would have been even 30 seconds longer that dog would have ripped me to shreds. I have never been so scared in my life, i swear my heart was beating over 200 beats per minute & i was shaking like an old lady.
I am just glad to be home safe & away from that dog! Now if only i could stop shaking & my heart could beat normal again!!