I had become poor like this once in my life. I had to ration my food so that it would last a week. I had to think many times before consuming anything as to how important it was for me. I had to think about transportation costs to interviews. I had to tell people that I couldn't pay them because I didn't have money.
One important thing I noticed that I became more superstitious. Like you mentioned, I kept questioning the paths I had traveled in my life, kept wondering if what I was going to do next was going to help or harm. It was really crazy. I could, of course, see that happening in myself, but the rationalization was, "what's the harm?"
I also think that's tied up with one's faith in oneself. And the eroding of that faith was quite surprising when poor. I guess some people have a strong faith in themselves. I didn't.
I also noticed that we focus on too many petty things in our lives. Social structures, peer acceptance, comparing ourselves for a sense of worth. None of these really matter at the end of the day (or life!).