Problems with "Exit Sub"

Hi everyone!

I have the following VBA code:

Sub UnlockPump()
MsgBox "This step can not be redone. Are you sure to proceed?", vbQuestion + vbOKCancel
If Answer = vbCancel Then Exit Sub
Application.ScreenUpdating = False
Sheet1.Unprotect
    Range("P33:Q33").Select
    Selection.Locked = False
    Selection.FormulaHidden = False
    Selection.ClearContents
    With Selection.Interior
        .Pattern = xlSolid
        .PatternColorIndex = xlAutomatic
        .Color = 10092543
        .TintAndShade = 0
        .PatternTintAndShade = 0
    End With
Sheet1.Protect
Application.ScreenUpdating = True
End Sub

I am beginner with VBA. All of the code which starts with a space I have recorded from a macro. The other lines I found on the web and copy paste it.

The problem about this code is that after the message box pops up, the sub does not end after clicking on cancel. So no matter that you click the macro just goes on.

Hope that someone can help me here.

Thanks!