M.G.
Hard day. Hugs.
Does she have anxiety? The vomiting can totally be from anxiety. A field trip can do it.
I recently chaperoned two little anxious kids. One was clamped on to the other the whole time.
Does it come off as infantile? To people who don't recognize it - probably. Feeding into it? Making a big deal - kind of the wrong thing to do. It often worsens it.
Is she young for her class?
Huge leaps at age 7-12-18 I think it is. Huge in terms of development. She's almost there.
The being depressed - is more likely exhausted. If she has anxiety and got home at end of day and was cranky and lethargic - that can be from dealing with stress all day.
I would ask your doctor and maybe just see a child therapist. Has helped me to understand better. Do not blame yourself. Do not beat yourself up. Anxiety is very real. There are tips and tools - if that's what this is.
I have one with low social awareness. Lack of empathy was the concern for me. But some of that is maturity. It's only a real problem if it interferes with relationships and causes problems for the family and at school. Therapy has been really helpful there, and also catching my kid doing good things for others. Rewarding the positives. So we have a jar where we put marbles if people do nice things for each other. When jar is full, we do something fun as a family. Each week you can pick a virtue to work on - and when you see it, you can give them a check mark, sticker, etc. Lots of ways to help this.
I suggest you talk to someone - it's a huge stress as a parent and you should trust your gut. A lot of it you can really help with the right tools. Best to you
ETA: If the vomiting was related to the bus only (and normally she doesn't get squeamish) she could of course just had motion sickness. I only mentioned the anxiety as some kids appear to be babyish (hate that word) because they find things daunting. Sensitive kids can come across as really young too.
Blow off the woman's comments. My mom was a kindergarten teacher her entire career. She saw everything. No-nonsense, practical approach - kind and reassuring, empowering the kids - was far better than coddling. Some people make a big deal (as this woman did). No need to upset you. I cut people like that off in mid-sentence, thank them - and just talk to my child after I've let it go.