Welcome to Android Central! When you say it's in the menu bar, do you mean the status bar at the top of the screen? If so, is it on the left or right side?
The notification log isn't the same as the notification panel. It's a little convoluted to access the log, but go through the process of adding a widget, and choose the Settings widget. When you place that widget, it will ask you what Setting you want -- Notification Log should be an option, so select that. Now tap the widget and see if that icon shows up as a notification.
But if it's on the right side of the status bar, it's not a notification, so it probably won't be there. It might be the Do Not Disturb icon. What happens if you increase the volume by pressing Volume Up -- do you see anything about Do Not Disturb there?