What does it mean if a girl sends me her photo?

This kind of behavior of a lady must be very obvious, indicating that girls really have a good impression on you, so girls want to associate with you, so they will send you her photos on their own initiative.

The most important aspect is to show that the girl's feelings for you are ok, so I think if you like this girl, you should still grasp the feelings with the girl, which is the most critical place.

So anyway, we should have a good talk with this girl and see how it develops.