Actually, try not to blow a load edging or get a dry orgasm. Edging should be used to get you to a full erection and even help make you last a hell of a lot longer in bed where screwing is the main thing instead of just reaching a nut. Also it will help in the long run to make you harder than a rock along with good kegel routines.

It is not uncommon to have either issues getting it down some for jelging or up a bit because your brain needs to adapt to the fact that you are doing an exercise so in time you will be able to control how hard you need to be in that exercise.