Did you try the challenge this week? If you tried, but found yourself stuck or blocked, what got in the way? What happens when you internalize writing expectation? Do you encounter bits of perfectionism? Do sink under the weight of anxiety?
Do challenges like this push you to write a lot, to do whatever you need to to move forward? If they do, good for you! Bottle what works, and use it to help you in the future.
If they do not, view your experiences with challenges such as this an opportunity to work on the psychosocial blocks to your writing and publishing success. Try to see your weaknesses not in a shameful light, but as part of what it means to be human. Doing so will make them easier to work on. When we judge ourselves too severely, we tend to find ways of defending against them. Face them gently, and commit to working on them, one at a time.