Thank you for reaching us out! I am glad to hear you are satisfied with Test Studio.
The idea of load testing against an application is to execute http requests concurrently simulating multiple users accessing the page. Since your application allows a single login per user it will be necessary to create real users to be used in the user profile.
Though a single profile for a scenario is sufficient as you can data drive
it and simulate different users executing the same http requests. Additionally the dynamic targets feature
could be of further help for you. Also you have the ability to add custom targets
as per the application specifics.
I hope this information will be useful for you. Though in case you need any further assistance, please do not hesitate to contact me again!