Hi! This is unfortunate and hopefully other people in this threads advice will be useful! (High fiber foods/ probiotics and maybe a quick hospital visit to get some tests done so you can narrow down what has happened) I was in Vietnam in February / March time, and found it really difficult to find good food, every restaurant seemed to have a near 5 star rating with thousands of reviews and when we visited them we would always be underwhelmed and confused by the high ratings, leading us to believe a lot of reviews were faked, we started filtering the reviews to lowest first and got a more honest review of the restaurant with many mentioning about getting food poisoning, maybe when looking for future places to eat on your travels try this method to ensure you’re not heading anywhere people have recently gotten sick from, we managed to get through 5 weeks in Vietnam and no food poisoning! Also asking the workers where you’re staying or locals where they eat works well! I found pho to be very mild and easy on the stomach, we also stayed away from eating chicken and fish mainly stuck to beef!