A Funny Thing Happened On The Way To Lunch

So yesterday I had lunch with a dear friend of mine at Crimson Cafe. We were to meet at 12:30 to fellowship and catch up on old times from the summer. I'm rushing in, thinking that I am going to be late, considering that I left the library at 20 after 12. As I'm dashing in, I review my plan in my head: I've got 25 dollars to last me until payday, and I'm going to order a salad and water. Combined with my discount, I should spend no more than $7. I plan to adhere to my plan no matter how my friend tries to persuade me; I won't get a dessert, I won't get a carbonated beverage, I won't even ask for extra dressing.

That is, until I get a call. 

"I'm running late, I'm so sorry. The thing is is that I forgot my wallet at home. Would you mind picking up  lunch?"

I'm stunned. My plan is shot to hell. But before I know it, I'm saying "Oh sure. Don't worry about it."

I started laughing hysterically after that.

Long story short, she has the nerve to order not only a more expensive sandwich melt but a carbonated drink to go with it. I end up spending about $15 of my $25, and then decide to blow the rest of it on gum, a Coke Zero, a bag of chips, and a loaf of bread.

There's about $2 left now. Hey - at least there's a payday in my future!

Now granted, if I had not had the change, my pride would have probably gotten me in trouble and I would have used my credit card or started stripping for a couple of dollars. Or claim that I already had a big lunch, just order what you want. 

What do you do when you are caught in a financial bind? How do you address it?