automatic close

hi every body i am new here and i have a question i work with excel so i want :

put a lebel on my workbook and when this work book is opend the label caption will be automaticly in minutes ( i mean the caption will be exemple : 5 minutes ) and when this 5 minutes in finished the workbook will be automaticly saved and closed .

so : the woorkbook will be automaticly saved and closed and elapsing time is appeared on this label

please help me i need it