Set AWS Cloudwatch Alarm datapoint timespan and action to shut it down

Follwing case:
We want an Alarm in AWS that reads the EstimatedCharges Metric of AmazonCloudWatch every 5 minutes (for potential log overflow). But the only timespan I can set are 6 hours, else it gives me "Insufficient" as Status. How can I change the metric so that I can use it with 5 minutes between each check?

And how can I make an action that will stop the Cloudwatch Logs when over X?

According to documentation.

CloudWatch Billing metrics are updated every 6 hours.

Thus, your Alert may change the status only every 6 hours.