How To Check For User Interaction Whenever Change Detected

I was told that the following code would enable my macro to execute every time the user interacts with anything Excel:

Code:
' Repeatedly check for user interaction whenever a change is detected
Private Sub Worksheet_Change(ByVal Target As Range)
Call TestMacro
End Sub

It doesn't work...

To put it into context, he is my entire program:

Code:
Sub TestMacro()'
' TestMacro Macro
'
' Create string variable
Dim undoText As String
' Assign the text to string variable

[Code] ......

My being new to VBA doesn't work in the situation as my programming instincts tell me to set up an infinite loop to continually check for interaction something like the following:

Code:
while( x == 1 )
{
do MY_CODE;
if( USER_CLOSES_EXCEL )
x == 0;
} // end while

However, Excel is apparently 'Event Driven' so I'd love to know how to use this to my advantage in keeping my macro running.