My first solo trip was too much.  I planned it like I planned all my other trips, except that there was nobody to help with the work!  It ended up being very long days.

By day 3 I had a narsty blister and was dead tired.  Heck, I hadn't even smoked any of my pot yet!  So I took a rest day, relaxed, read Steppenwolf.  Ironically that's the book I read on my last solo!  ~15 years have passed, so it was interesting to re-read it as someone entering middle-age.

The next day I woke up early and knew I was done.  There were still a few days on my itinerrary, but I was done.  So I packed up my gear and checked the map for the most direct route out.  It was further than any of my previous days, but I was motivated and made it home that night.

My first solo trips were all shorter than planned.  Each longer than the previous.  Something inside always says, "Time to go!"  I think my maximum is 9 or 10 nights, that was in Q 2 years ago.  My minimum is 2 hours, I just wasn't feeling it.

Other things I remember about that first solo was overpacking. 
Way too much food.  I just don't eat that much when I'm alone.  Sometimes I have to force myself to eat for nutrition, not for hunger.
I also packed a lantern, what a waste - a tool that simply ruins my night vision.  Used it once, carried it for days.