----- Not an ESL teacher -----
Some context is needed but maybe you could spot the following difference:
The first one could refer to a shorter period of time. For example, you waited for your date for about one or two hours, or perhaps all night long, and she didn't show up.
On the other hand the second one could refer to a longer period of time. Let us say you waited for the girl of your dreams for several months or years and she never appeared.
PS The only thing in your post that disturbs me is the "Cud u" part. That would really read better as "Could you".
Student or Learner