20 days to Marathon #4

Please forgive my tardiness in posting...
We returned from the Happiest Place on Earth on Saturday and I'm just now feeling caught up with things.  Needless to say, Disney was "magical" for the kids!  And it wasn't too bad for the adults too, but it was not ideal for marathon training.
While I'm sure I walked around 10 miles each day for 4 straight days, it was not the type of exercise that does much good for endurance racing.  My legs and feet HURT at the end of each day, and the 18 hour bus ride wasn't exactly good for my muscles coming or going!
Returning on Saturday meant I missed my 20 miler...again!  This is my greatest concern about this training period.  Having missed the first 20 two weeks ago, this was supposed to the confidence builder I needed.
I had no business going out to run on Sunday, but I had to do something, so I opted to literally run to the office (2 miles) and catch up on some work, and then take a longer route home to get me to 5.5 miles.  It just didn't feel like enough, so I tried to fuel and hydrate into Monday and then after work Monday took off for an "endurance test".  I knew I had to get at least 10 miles in, but wasn't sure how much further I could go.  When it was all said and done, I only got 11 in.  No where close to the 20 I should have dug deep for. 
To make matters worse...I didn't cool down enough, so I dealt with some pretty bad back pain for the rest of the evening. 
Today is Tuesday and I'm resting, but I'll get out and run in the morning, and maybe once more before the weekend.  Saturday is the Henry County Half Marathon, but just hoping to repeat the Sam Costa effort there.  Then the real taper is on...Hope I'm ready for all this...