Girlfriend has gone out drinking with a friend, had a few issues in past when drunk. Wondering if I should have any reason to be worried?

So not sure what replies I will get, just wondering if I am overthinking. So hoping to get peoples thoughts

My girlfriend has gone away to see family and see one of her best friends, we met up with another one of her friends, which I was going to meet for the first time and it turned out she had been drinking since like 1pm and turned up half drunk to dinner and then wanted to try and drag us out to drink. The best friend she is going to see supposedly likes to drink till late and party.

In the past, we have gone out a few times drinking. Something has always ended up happening, for example the first time. My girlfriend likes to be touchy feely when drunk... we started speaking to this guy, she ended up patting him on the chest when saying something and shoulder, he took it as she was into him and wanted more, ended up with him saying he wanted to f**k her. She was drunk and carried on as normal chatting to him and ignore what I said about it, didn't remember and realized next day when I said.

2nd time, we were out and she put her head to someone else's head staring into each others eyes, was already awkward as I had my friend there and he was finding it strange and was shocked. She said it was due to the other guy insulting her or something, but then carried on chatting as normal. He tried to touch her breast and she pushed it away, he was a d*ck and had a girlfriend, with her being touchy feely he took it as she wanted him and said she wants me i'll fight you for her and about him wanting his girlfriend to have a lesbian experience. We left shortly after and she was upset and mad at me, my friend went as he just found everything awkward and next day she couldn't remember anything again.

While away she is now drinking with her best friend, had 3 Guinness within an hour, first thing they decided to do after so long and I feel awkward about it. She keeps saying "if I am going to have a guiness I need multiple I can't just have a few"
Girlfriend has gone out drinking with a friend, had a few issues in past when drunk. Wondering if I should have any reason to be worried?
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