API Gateway get_usage API doesn't return results until quota limit is reached

I have an API deployed in the API Gateway. I also have an API Key and a Usage Plan with a quota associated with the API. When executing the API, the get_usage API returns no results initially. There is no usage shown in the API or in the console where Usage can be selected.
it isn't until I run enough tests to max out the quota and get the "Limit Exceeded" message that the get_usage API returns results. Has anyone seen this?