Could this be schizophrenia?

A few days ago I began to hear voices in my left ear. I was reading something and came across the word 'certain', yet it was spelled without the 'a' on accident. All of the sudden I heard a cheesy version of an old woman's voice; the type you would hear in a cartoon. She was saying something, but I couldn't tell what. The only word I could actually make out was the word 'certain'. I was confused, since this wasn't from my own thoughts, and it was almost as if my left ear was actually hearing it, yet it was still far from sounding like it was coming from an external source. It couldn't have been anything else to my left since the wall was three inches away from my left ear! I continued to hear things, and yesterday or two days ago I heard a loud voice right in my ear. It was as if my thoughts had been briefly amplified to where I could almost hear them outside my head. Two days ago I was sitting in my parents' bedroom watching TV. All of the sudden, I heard a loud whisper that made me just about jump out of my skin! It had scared me, because I thought it was my mom, but I hadn't seen her walk in. I thought she was still in the kitchen, where I could almost see her from where I was. I stood up and looked around the room. Nothing. No one was on the bed behind me, where the sound could have come from. No one else was there with me. The whisper was so real, and it did NOT sound like it came from my head. It sounded like a normal noise, maybe not exactly a normal whisper, since it was loud and I couldn't identify the one-syllable word it spoke. Today I had another scare while I was (ironically) looking at a site for people to share their psychic experiences. I looked in the reflection of my screen off to the side at my window sill behind me. Something seemed to be moving. I looked behind me. Only the curtains were moving oh-so-slightly. I turned back and forth a couple times to try and find what I was seeing and to catch it in the act of moving just like its reflection. After my failed attempts, I looked into the screen again and saw a large cat-sized shape seeming to walk across the sill, yet I still didn't see anything when I turned. My heart started to beat faster and I started to breathe deeply. I somehow very frightened from this. I left the room and went downstairs to eat something. About five to ten minutes later I was in an okay mood and was going upstairs to exit out of the websites that that were still open on my computer. When I got to a certain step (I don't know which one it is) my happy mood suddenly vanished and I felt this rush of fear and dread. This was probably because that probably was the first step that could actually be called 'close' to the second floor. I'm not sure if this is related, but I very often see random people out of the corner of my eye, but I know I'm imagining them because I can't imagine faces, and they have never had faces. Do you think this is just my mind playing tricks on me, or is it more than that? What about the whisper in my parents' bedroom? Was that even real?