I ran 15.8mi by accident!!

Nice going. Makes for a good story ... and the kindness of strangers has saved me many a time.

I got lost during a half-marathon, to the tune of an extra 6 miles or so.

I also got lost during a marathon, but that cost me less than a mile. Still, it was near the end, and ANY extra yardage at that point is terrible. 

I might take it easy for the next week or so.  You weren't trained for 16 miles and you might need some recovery time.  Glad you made it!

+1

Building slowly is obviously preferred.  Definitely get some extra "recovery" in for the rest of the week and keep your next few runs "easy."

Don't worry about how you will feel running 26.2 based on your first 16mi run; especially given you jumped from 11 miles.  As your training progresses, hopefully in a more measured build, those 16 mile runs will become much easier.

Good luck with your training.

When I first started riding when I lived in Germany I would specifically go "This turn looks good."  Then the next one, and the next one and before you knew it I was lost - on purpose ........

Since I lived near the airport I'd just look up and see which way the planes were going and try to make my way back using them.  I only had to ask for directions once.  Some of the best rides I'd ever had!

I still try to go out and get lost occasionally, but since I know my area really well it is harder and harder to do.

Congrats on the great run!  Rest and recover and go out for more!

I do this on the bike all of the time - kind of like Rick was talking about.  I did it way more when I lived in a farm house that was out of town away and I didn't know all of the county roads very well.  I would load up as much water as I could and take off.  Every time I passed a decent convenience store I would get more water if I was running low.  Nice long rides and you get to see a bunch of scenery.

I have never done it running, though.  Mostly because I don't ever run far enought to be able to get lost.