For the last 3 days I've been having burping constantly. Sometimes it feels like there's something blocked in my throat not letting the gas out and my stomach also feels very odd like its churning. I'm scared of vomiting and when I feel a burp coming I'm worried I'm going to bring up food. I don't know what's causing it? It doesn't matter if I've eaten or not. There's just constantly something coming up my throat like I need to burp. Does anyone know what this is?