I had so many funny and lovely for more than 30 min, that too in before I wake up loll. Bad dreams do not last more than 10 min I think loll. This is purely my perspective loll.
This picture will answer a lot:
Right up to the good part then you wake up,are if you fall right before you hit the ground. It gets confusing though i was making a deposit at the bank once and it was robbed during that time and i could actually feel the bullets hitting me and i didn't wake up until i helped catch the bad guys. So it's really confusing on how long they last .