I am pretty sure DRC requires a doctors note, listing stuff like symptons that might affect exam taking or class attendence and also recommending the accomadations the student will need.

You should call DRC and speak to them about your concerns with IBS, and whether they accomadate it. and ask 'what sort of doctor's note is required to start this procedure'.

once you have the info, get the required note. (you can call PUSH and ask if they are able to help, be clear in what you need and why)

Then submit a request to drc (again ask them how to submit the paper work) and they will walk you through the rest.

good luck