Can't find the "event"

[Android Question]

I am a newbie with a Samsung Galaxy S4. In the last few days I am getting the square icon with the number one which I understand means there is an event it wants to notify me about. Then it gives off a sound that is probably telling me the same thing. Initially it occurred every couple of hours but lately is more frequent and is driving me crazy.

I have checked my calendar "S Planner" but there is no evidence of anything.

How can I translate that icon and sound into the event so I can turn it off??

 

[Rukbat]

Pull down the notification bar (top of the screen). Look at the bottom of the list for notifications.