Hosting your first event means worrying nobody shows. Five people who came are a start, not a failure.

Attendance at a first anything is low, and the number tells you almost nothing about the idea. It tells you how many people had heard of it and were free. Judging the whole venture by that count is judging a seed by its first week in the soil.

Count the room you actually got and treat those five as the people who will bring the next ten. Ask each of them one thing that would make them return. Run it again soon enough that the second one arrives before your nerve wears off.