I noticed that when my.mind was busy thinking it dtowned out the wobble. So I intentionally focused on listening to the wobble, which minimized thinking.  Tho no sleep, got good rest. 
I couldn't tell when we entered Theta, but "felt"  the beginning of the shift  towards  Alpha.
Good job! In lieu of a proper "nap," a little mindfulness goes a long way. :)
Kathryn Bynum