I have one co-worker here in Saudi Arabia, also a Filipino. It was before the pandemic, he was having delusion of being threatened by anybody around him that includes us since we are living in the same accommodation. He also has the feeling similar to Amy that something is in his intestine. We ran him twice to hospital, the 2nd time was worst he almost jump from the 4th floor, he felt someone is going to hurt him.
Thankfully, he's now okay, I hope he is totally okay.
It can feel very real, and sometimes frightening for people, depending on the delusion.
Yes, it can be felt so real as myself experienced anxiety just last year. Before that, I wasn't really convinced of the so called "anxiety and depression" until I have it. It is easy to advice people who are having anxiety, depression, delusion or any other psychological problems but it's hard to get out when you are there. But for me, the best doctor is yourself, you just need to win the battle. Nature and get surrounded by positive people will help you out from it.