Can I use a workflow to send notifications right away?

You can use a workflow to send notifications within minutes of relevant events.

First, a History report will need to be set up with a Creation Date field that is filtered to show only the transactions that have been created "after" "minutes ago:" "5" (for example). This report will be used as the criteria for the workflow.

Then, a workflow can be set up with a Time trigger of every 5 minutes (matching the amount of time set in the report filter).

Check that the report contains rows in the criteria section, then add an email or SMS action to send a notification to the appropriate user or group of users.