Constant nausea, no stones, can it be gallbladder related?

I have been having daily nausea since the end of December. Sometimes accompanied by a gnawing feeling in the chest. Some days I can barely eat because of the nausea. I have had an ultrasound witch showed no stones and a endoscopy which out ruled acid reflux and ulcers. My doctor said that maybe my gallbladder isn't functioning right so he put me on a medicine called actigall which is supposed to help thin the bile. I've been on it for the three weeks he recommended and it's not getting any better. I had a HIDA scan today to check the function I will get the results from that on Monday. I never have any pain. I did start getting a dull ache on my right side. It doesnt last long and has only been happening for about a week. I have eliminated fatty and greasy foods from my diet since January and still the same problem! Does this sound like a gallbladder issue? Or something else. I'm literally getting depressed and just ready for this to be over! I feel like I am having a night mare and can't wake up. I have 3 kids (1,3,4) and a loving husband and I feel like I can't be a good mom or wife right now because I always feel so sick:-(. I am only 23 years old. I never thought I would be going through this. I went through something similar in 2009. I had bad nausea and heartburn lost 25lbs and it was about 9 months before they diagnosed me with gerd. I took prilosec and got better. Now 3years later it's happening again but the nausea is worse this time around. Does anyone have any advice?