Get Request List by Requester from API

I accidentally posted this topic in the SDP-MSP forum, but I think I meant to post it here.

Here is what I'm trying to accomplish:

When there is a problem with our software, users will send an e-mail to an e-mail address that we have set up. That e-mail creates a new request/ticket in ServiceDesk Plus.

When the user/requester logs in to our third-party student/faculty portal, they will have a section titled "Open Tickets". This is where I want to display only the ServiceDesk tickets associated with that user. When logging in directly to ServiceDesk Plus, I can click on a requester to get all their requests. I want to be able to get this list and all of the associated details to display it to the user.

this is the query string that I'm passing to the API:

http://domain:port/sdpapi/request/?OPERATION_NAME=GET_REQUESTS&API_KEY&INPUT_DATA=<details><from>0</from><limit>5</limit><filterby>All_Requests</filterby></details>

Which i expect should return the latest 5 requests, but instead it returns the latest 25 requests. How do I get the limit parameter to work and how do i filter by requester.

Any help is greatly appreciated. Thanks!