help! throwing up mucus

I am 13 weeks, from the begining, 3-5 days a week when I wake up in the morning I have severe post nasal drip. I begin to cough, which turns into gaging and throwing up which consists of a bunch of mucus and bile. It's like all night my sinuses are emptying into my stomach then in the morning my stomach can't take it and it all comes up. It's usually every other day. Usually when I shower because it gets everything moving but sometimes it happens before. Anyone experience similar symptoms and have any ideas for relief? It's terrible since throwing up actually causes nausea, headaches and just generally feeling like crap for the rest of the day. Please help!