You ran into the rolling rate limit. It's a bit of a roadblock designed to make sure you understand the purpose of the site before you ask any more questions. Taking a moment to ask here on meta is a very good step in that direction. In addition, the current state of your questions seems promising.
That said, the block can't be removed—it must be waited out. Even as an employee, I can't lift the restriction. The message that explains the details of the block points to an answer that describe the calculation:
It's based on your average question score, how long you tend to wait between asking questions, how well you participate in other ways on the site, and how often you tend to revisit and improve your posts, even the positively scored ones. We don't provide the actual formula and details, only because we want folks to focus on what the system is trying to tell them, rather than trying to find ways around it.
Rate limits vary from 1 to 7 days.
This block is intended to address the common problem of someone who does nothing on the site but ask a series of poorly-received questions in rapid succession. In the past, that would lead to users running into bigger problems, such as an extended suspension.
Again, it looks like your questions are better than they initially appeared to the system. This might have been a false alarm.