Trouble on the Train

This morning when I changed trains, I found a seat which nobody sit.
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This morning when I changed trains, I found an empty seat, so I sat there.
◎an empty seat

A man wanted to sit there too, but he couldn’t because I sat there before he sat there.
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A man wanted to sit there too, but I was already sitting.

He seemed to be upset. He stared at me strongly.
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He seemed to be upset and stared at me intensely.
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He looked upset and glared at me.
◎glare at 〜: 〜をにらみつける

I heard that he took a picture of me. I heard the noise of shutter.
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I heard the sound of a camera shutter, so I thought he took a picture of me.

◎the sound of a camera shutter 

So I couldn’t keep sitting. I was upset.
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So I couldn’t keep sitting there. I was upset.

I stood up and said, “Could you sit here?” He answered “No!”

I asked him, “ Did you take a picture of me?” He answered “No!”
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I also asked him, “ Did you take a picture of me?” He answered “No!”

I thought he took a picture. He lied.
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I thought he had taken a picture of me. Maybe he lied.

Other seats were empty during we were talking .
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Other seats opened up while we were talking.

◎opened up: become available, offer because someone left 

I said, “Could you sit there?” So he sat another seat.
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I said, “You can sit over there.” So he sat in another seat.
◎sat in another seat

I didn’t take his seat away, but he thought I took his seat away.
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I didn’t mean to take his seat, but he probably thought I had taken it.
◎I didn’t mean to 〜: 〜するつもりはなかった
◎probably thought: きっと〜と思った
◎maybe(less certain) →probably(quite likely)→definitely(certain)

Am I wrong? Could you become my side?
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Am I wrong? Are you on my side?
◎ Are you on my side?: 味方になってくれる？