Well done for gettng to your first meeting.
It's fine not to share in the main meeting. Plenty of people don't always share. Some peope never share in that way. As you get to know a few people you will maybe find it easier to chat one to one. And, if you want to talk more openly, once you have found people who you most relate to and trust you might find yourself doing that as well. We can learn a lot from listening.
BB