Initially I was broke. When I got my first real job (after undergrad in India), I felt like I had all the money in the world. In the first few months, I bought myself a nice camera, motorbike, smartphone, gifts for family and my girlfriend, started eating at nice restaurants etc. But then I figured I already had whatever I needed and things I enjoyed most didn't really require any money (except the camera and motorbike, I guess).
Then I quit my job and went to grad school for which I had to pay for (Masters, not a PhD) and went into debt (US schools are sooo expensive), and drastically cut down my expenses (ate cheap Thai food almost every day). After that I got a well-paying job again, paid off all my loans, and am now back to my earlier lifestyle i.e. I spend on things I enjoy, give a modest amount of money in charity regularly, enjoy the occasional expensive dinner, buy nice gifts for my family and close friends, but I still save a good amount.
I am definitely happier than I would be without any money, but I don't think I would be any happier if I suddenly started earning 2x.