Configure Webhook as Data Source in Grafana

I have an existing webhook application sending data. I need to configure the webhook as a data source within Grafana so I can make data visualizations. I already have Grafana up and running and I installed the Flowhook plugin with Grafana. I also have the webhook working with https://flowhook.herokuapp.com, but I am unable to connect herokuapp.com with the plugin. There may be a better way to do this, so I'm open to suggestions.