Creepy story

My step mom got married to my dad when mom left. My step mom was actually friendly and caring at least for as long as I knew her, that was how she was to me. But ever since she stepped into our house was when things started happening. I was in the hostel when the bad news that dad died got to me. I wasn't really shocked but what shocked me most was that he was bitten to death by a dog which was weird because dogs weren't common in our area. I tried to find out about the dog that bit him but step mom told me to forget about the issue which I did reluctantly.
Ever since then, I started having this dreams were I was being pursued in my dreams by a beast looking dog. I told step mom about it but she said it was because I was thinking about dad's death. Once I had the dream but this time it was more real. I was being pursued by the beast looking dog which later caught me and bit my arm so hard that It felt real. I saw an axe in my dream which I managed to grab and as the dog was about to run away after seeing me with the axe, I leapt at it and managed to cut off both its hind legs. It later escaped crawling away. I woke up feeling pains all over my body, I looked at my arm and I saw teeth marks on it with blood coming out, feeling scared, I decided to tell step mom about it. Getting to step mom's room, what I saw shocked me more. Her room was bloody and on the floor were two amputated hind legs of a dog, exactly like the one in my dream. And beside the bed was step mom crawling towards me without legs. Her body was still dog like, exactly like the dog in my dreams. Now I knew why dad died from dog bites.