Interpreting body language and nonverbal cues can be tricky, as they can vary from person to person, and sometimes, it's hard to pinpoint a specific meaning with absolute certainty. However, I can provide you with some potential interpretations of a girl smiling with her mouth closed when you say "hey" to her and then mention her name:
Shyness or Nervousness: Smiling with a closed mouth could be a sign of shyness or nervousness. She might feel a bit uncomfortable or unsure of how to respond, so she smiles as a way to acknowledge your greeting without saying much.
Politeness: The smile could simply be a polite response to your greeting. She may not know you well or isn't in the mood for a more extensive conversation, so the closed-mouth smile is a way of acknowledging your presence.
Reserved Personality: Some people have a more reserved or introverted nature. Smiling with a closed mouth might be her natural way of expressing friendliness while still maintaining a degree of privacy.
Mixed Feelings: The closed-mouth smile might indicate mixed feelings. It's possible that she is happy to see you but is also unsure or hesitant about something else, which can reflect in her body language.
Cultural Differences: Different cultures interpret body language differently. In some cultures, a closed-mouth smile might be more common or considered appropriate in certain social situations.
It's crucial to remember that interpreting body language should be done with caution, and it's always best to consider the context and other factors. If you're interested in getting to know her better or understanding her feelings, the best approach is to engage her in a friendly and respectful conversation. Over time, you may get a better sense of her personality and intentions. Remember to be patient and considerate, as relationships and connections take time to develop.