I’ll give you both perspectives and you decide

I’m just confused. Everything that happens I’m always the one being wrong but I can’t see it. So here’s something we argued with my sister just now, both perspectives. Please tell me I’m not mean.

So what happened: yesterday we went to shop at a mall, and we went to shop a last minute outfit for NYE where we tried on a couple of trousers. I didn’t find anything, but she did so we bought it. At the point we exited the shop, she was like “So are we finished now? Are we going home?”

My perspective: I immediately thought it was a selfish move of her because she has bought what she needed and didn’t even appreciate that I wasn’t finished with my shopping, so just because she was finished it meant that we would go home. Then she acted tired the whole time, and I had to rush my shopping to bring her home.

Her perspective: She claims that she wasn’t selfish, but she was tired. When I was asking her during our time there why she was angry she answered that shes not angry but she’s sad.

Basically what annoys me is that instead of her trying to enjoy her time with her sister, she only complained, let me talk to myself, and reminded me the whole time how much she hated that place (ie. any place that has shops and people), something that I cannot understand. I hate overcrowded places too but when I’m with someone there’s my chance to enjoy it and avoid social anxiety. She acted like she WANTED to have social anxiety. I bought her coffee and clothes and she showed zero appreciation. I haven’t heard even a thank you. The only thing I heard was 10% “I’m sad”, 10% “I want to go home”, 10% “I hate malls” and 70% silence. I don’t know what to do to her. She is unpleasable and selfish to me.