burping 5 days non stop.

20M, Hi i’ve been burping non stop for the past 5 days, i’ve been to hospital as it’s causing me chest pain from the strain but they were unable to tell me what it is, nothing i do gets rid of these hiccups that last up to 4/5 hours a time, ill get maybe an hour break and then straight back to it, my diet has changed dramatically from hardly eating 1 meal a day to eating 2/2.5k calories a day, really struggling to sleep and do normal life things because of these hiccups, is anyone able to help me please!