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I've been dating a guy for about 3 months. Things have been going really well, we text every day, see each other a few times a week, and have even talked about future plans.

Last weekend we were out with some of his friends. At one point he left his phone on the table while he went to the restroom. A message popped up from a woman with a heart emoji next to her name. I didn't open anything or touch his phone, but I definitely noticed it.

Later that night, I casually asked who she was. He immediately got defensive and said, "Why are you checking my phone?" I explained that I wasn't snooping; the notification just appeared on the screen. He then said it was an old friend and that I was making a big deal out of nothing.

The thing is, I'm not even bothered by him having female friends. What bothered me was how defensive he got over a simple question.

Now I'm wondering if I'm creating a problem where there isn't one, or if his reaction is actually the bigger issue.

Would you consider his response a red flag, or am I overthinking this?