It never ceases to amaze me how fast things change on longish rides.
At the onset, biking is FUN!! going FAST!! those hills are hard but give a great sense of accomplishment.
Then the switch flips, and I'm wilting fast. Then - off the bike, sitting on the curb, and crying.
Yes, always bring food, water, money, id, cellphone.
I keep a powerbar in a flavor I don't even like in my saddlebag. They are edible for months.