Must vs. Want

How often in my head I hear: "I must do it! But I don't want!
How often in our life do we put Must vs. Want!
How easy is life with Want and how difficult it can be with Must!
This happens often we you need to do something routine, when you need to meet deadline, when you don't have inspiration, when you are working and thinking under pressure.

Now in my life I face this pressure again. It happens with Sketchbook project I am participant of.
The point is that this project unites people all over the world who like to draw sketches in Moleskine [or other] notebooks. Some of my previous sketchbook you may find at www.issuu.com/AnnASKryabina.
I was supposed to receive my notebook almost 2 months ago. But due to post office or other problems, I received it only yesterday. And there is less than 10 days [instead of 2 month] before deadline to draw almost 100 pages of sketchbook. And I didn't even start!
I love to draw and I really appreciate this project. But I feel under pressure even I should not. It is one of the most enjoyable thing ever! But I must have inspiration to draw. I can not buy it or order, also It doesn't work according to timeline.
I started to search in the internet about Must and Want. And I understand the point. But how can I make myself not afraid of meeting deadline and searching for inspiration? How can I relax and enjoy?  
"The more you feel that you have to have something and the more emotion you put into clinging to that thing, the more you push it away. Neediness creates a mindset of lack in your life instead of a mindset of abundance. Neediness causes us to become attached to a specific idea or outcome. Becoming attached to anything always causes emotional distress". [More here]
Do you have any good advise how to overcome this Neediness/Must and just Want?