Andy Ihnatko says there’s no such thing as writer’s block:
As a writer, you are never “blocked.”
The fact that you’re not actually writing doesn’t mean that you’re not actually working. You’re also working when you’re thinking. Figure out what the problems are and solve them. Solve them in a half-assed way if you have to; slap enough duct tape over the problem that you can proceed to the next step. Go back later and improve it in the editing process.
Sometimes, writer’s block is part of the process.