Hi Iv e had this test and it isn,t very pleasant. I had pain but that was because I have gastritis. It is very uncomfortable. You will be better staying in hospital as you will get reassurance from the nurses. They would also be able to monitor it all properly,as you have to write a diary of symptoms and when you eat,sleep etc. You will get through it,it is a long 24 hours but you will be glad when it is over. Hopefully you won,t have serious reflux.
Welcome to the gastroenterology community! Will a parent be there to help you through this? The test is not that bad. The tube is uncomfortable and annoying, but it shouldn't cause you much pain.