VS

Here are two versions of my first 250 words.  I am wondering what you guys think.  Do you like the first version or second?  Or should I rework the whole thing??
I couldn’t shake the feeling that someone was following me. Watching me.  As I walked into the usually bustling lobby of the building where my doctor’s office was located, I saw that the room was completely empty.  I felt a chill come over my body. Thoughts of horror movies came to mind. I was in that moment where everyone watching would be yelling at me, “GET OUT!”
I tried to rid my mind of these ridiculous thoughts. I was a fifteen year-old girl going to my annual check-up. Why would anyone be following me here? I walked to the elevator and pushed the up button. As I waited I scanned the room around me and saw that I was still alone. I began to laugh at myself. I needed to stop watching those cop dramas right before going to bed every night.
I realized I had been so lost in my thoughts that the elevator was standing open, waiting for me. I quickly made my way on as the door began to close behind me. I turned around and leaned against the back of the elevator as I faced the door that slowly closed before me. I was relieved to be out of the creepily quiet lobby and hoped that the weird knot in my stomach would go away. Just as the door was about to shut completely, a hand jutted into the small opening. I jumped. I imagined a serial killing maniac with a butcher knife on the other side of the hand and backed up into the corner of elevator.
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My footsteps echoed through the empty lobby. The uneasy feeling that I was being watched held on like a limpet to a rock. I quickly pressed the up button on the elevator and tapped my foot impatiently as I waited for it to get there. The distinct ding of the elevator arriving made me jump. As soon as the doors opened I scuttled in, glad that I would be in my familiar doctor’s office soon. Just as the door was about to shut completely, a hand jutted into the small opening. I recoiled. I imagined a serial killing maniac with a butcher knife on the other side of the hand and backed up into the corner of elevator.
In the moments that it took for the elevator door to open again, my mind went into full argument mode. Part of me was telling me I was being absurd. I had been on this elevator many times before. But the other part of me was almost sure I wasn’t imagining that someone was following me. I stuck my hand into my purse wishing that I had listened to my dad and carried the pepper spray he had given me as “my little girl is now in high school” gift. Instead I found my wallet, lip gloss, and a pen. I grabbed the pen, not sure what I would do with it, and held it in my purse as the door finally opened completely. I looked out of the door and saw no one there.
Any and all input would be great...Thanks guys :)