Waiting to hear from an agent and knowing that the answer will most probably be a rejection is a stomach curdling feeling. 

Waiting to hear from beta readers is also a nervy time...really, since you know they won't really say what they really think!!  I would always say positive things, as my dear friends do, but they are biased and kindly disposed towards me.  The bottom line is the bottom line...will it sell?  Will people part with their  hard earned cash to read it?

I've begun the next one, but the energy for it has flown somewhat, as the effort of the first was huge.  Maybe I just need to do something else for a few weeks and let my head gel together again.