Confidence is in the eye of the beholder. You may think everyone there was confident, comfortable, in control... but I can bet there were others there who were not.
One thing I've found is the first time is the hardest. The second time is "been there, done that", the third time you are welcoming someone else to the group who is seeing everyone as confident, comfortable, in control...
The first time I went out en-fem (Disney at night) I was scared to death and looked straight ahead. The second time, I went into a bar and ordered dinner and talked to the bar tender for a while.
Go again and you will see that your confidence will be up and the time after that you will wonder what the big deal was.