Just experience what it's like to spontaneously share your thoughts and feelings. This is a different way of relating to audiences than you're probably used to. When you're finished, continue to stay connected and acknowledge your applause. And don't start walking back to your seat until the applause has completely stopped. But suppose you go blank and can't think of anything to say.
Most people have a deathly fear of getting up in front of a group and then suddenly going blank.
Your three and five minute speaking opportunities are yours to do with as you wish. You do not have to worry about being interrupted or having someone jump in and fill the void for you or correct what you've just said. If you like, you can even stand in silence for the entire time. It's also reassuring to know that at the end of your five minute talk, you're going to get positive feedback no matter what you do or say. So you don't have to do anything to earn anyone's approval.