Is it possible to give feedback immediately after the answer to a question is submitted?
Not with the Canvas quizzes, no. The issue is that grading does not occur until after the entire quiz is submitted. So I can't conceive of any way to do what you are asking with the current quiz tools (but it's a good idea). It looks like there might be a few feature requests already to be able to do this. Here is one which you might consider voting up and/or commenting on Submit multi-question assignment question by question.
Retrieving data ...