I think it's wrong that email confirmation comes hours later after a response has been posted.
Can't the CRON task be set to run quicker?
Notifications about answers to your questions are not sent immediately.
When asking a question, if you want to be notified by email about answers, there is a UI for that:
You will note that the minimum schedule is every 3 hours, so it is fair to expect that notification about getting answers are not immediate.