If worry and being miserable would help out with the Phd experience, then I would say embrace it. But the truth is that its not going to help, and speaking only for myself, my own work is so much better when I am relaxed and happy. So, at the risk of sounding a bit Pollyanna-ish, I DO try to :-s:-s:-s make myself be happy. It can be done. ( even after having a carton of 15 eggs leap from its precarious home at Bleak Towers and rain yolks down my toes, when all I wanted was a cup of coffee....) Its as simple as finding something that makes you smile or laugh. We all have different things that will do this, find the thing that works for you, and do it. Arrrrrrrrr, it can be as simple as talking like a pirate! There, thats got a smile back on my face just like that!
I am not advocating from hiding from reality or being in denial ( or am I?) but the attitude you permit yourself to have can be key. I am cheerfully doing a bit of work on Saturday, having removed egg yolk from my toes, and treating myself to an extra cup of coffee....
http://www.inspirationandmotivation.com/
Act as if you have already achieved your goal and it is yours."
- Dr. Robert Anthony
"Optimism doesn't wait on facts. It deals with prospects. Pessimism is a waste of time."
Norman Cousins
"People are just as happy as they make up their minds to be."
Abraham Lincoln