Why do you feel anxious when you send a girl a WeChat and she doesn't reply for a long time?

That's because you like each other, or you care about each other I know this feeling best, because I have had it before. When you like the other person, you expect her to see your information, then call you back and continue to interact, and then you will be very happy and feel good with her. If she returns slowly, or doesn't return for a long time, you will feel that the other party doesn't take you seriously, and naturally you will feel uncomfortable and even anxious. You stare at your phone from time to time, and when it rings, you will check whether it is from her. Feelings are also prone to cracks and quarrels at this time, which needs attention.