The worse time to find out that your air mattress on has spring a leak is when you are sleeping on it.
I found that out twice this month in two different places with two different air mattresses – lucky me!
Fortunately, it is very easy to patch a hole in an air mattress. The slightly more difficult thing is to find the hole in the air mattress or at least it was for me, since the hole in my barely three month old air mattress was a tiny pinhole.