A trick I read about on these forums several years back, Tie your tube in a knot at the puncture, reinstall, and go.
I double flatted once, had 1 spare tube and some crap patches. I did the knot trick and made the 6 miles back. The next morning it was flat but it was getting changed anyway.
I expected to feel a lump/bump at every rotation but surprisingly it was quite smooth. It is a pain to stretch the tube the extra amount but it saved me from walking.
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nine mile skid on a ten mile ride