Well, your interest comes when you do something with your HBD savings. That means, you won't have an interest event if you just let your savings sit. You have to deposit or withdraw. Interest comes every 30 days, so if you withdraw after 30 days there will be interest. You can check at https://hiveblocks.com/
You will see this on the left
It shows the, "Savings hbd last interest payment". 30 days after this date is when your next interest payment will be. Either deposit or withdraw after this date and you will receive interest. It will show up in your https://hiveblocks.com feed for you to see it within 1-2 minutes after the event.