Crashed after 37 hours

After completing 37 hours, i set the alarm for 11.40 pm in my mobile phone but could wake up only at 12.50 am. I was unhappy on myself why I opt to take a little nap when it was not too late in night. I found now, 11.40 am, that alarm was on .. time put was right.. but the date is next days .. OOHh A good real life joke. Will try again.