What Causes Severe Stomach Pain With Nausea And Acid Reflux?

I am having severe stomach pain, nausea, vomitting, acid reflux and have seen several doctors and made several trips to the ER. Endescopy showed nothing wrong, stomach emptying test (starting digesting at 43min), and ultra sound. I spoke with my older sister in Canada and she said she is allergic to the hormones in all birth controls, could my Mirena IUD be the problem? I have had it for nearly 3 years and my conidition seems to be getting worse and worse. I tried to find my IUD strings today and couldnt find them.