flu like symptoms for 7 months now pain in ribcage and abdomen esp right side

For the past 7 months, I’ve been experiencing flu like symptoms on and off. Over the last 2 months, I’ve had major issues with dizziness, lightheadedness, loss of balance, loss of concentration, slurring speech and mispronouncing words. I’ve completely lost my train of thought while at work and during conversations. I feel like I’m in a fog. I have weakness in my legs, especially knees and ankles. Over the past month, my lymph nodes on my right side of jaw and under my arms have become swollen. Over the last week, I’ve had pain in my ribcage, slight lost of appetite, low grade fever, mouth sores, pain in my abdomen especially the right side, along with flu like symptoms: fatigue, ear pain, sore throat, headaches.

I’ve been to a number of doctors. My blood work is normal(I’ve been tested for mono twice). PET Scan was normal, it did say something about my gallbladder but the doctor did not think that what was causing this. The neck sonogram found swollen lymph nodes and scar tissue. I had a biopsy of the lymph node(just to be on the safe side, I had Leukemia as a child) and are awaiting the results. I also had a chest x-ray and a MRI of my brain that I’ll get the results next week. I’ve seen an ENT, a Rheumatologist, a neurologist, an oncologist and I’m going to a gastroenterologist next week. Nobody can give a straight answer about what the heck is going on. This illness is interfering with my job and home life. Does any one have a suggestion as to what doctor to see next? Does any one know what might be wrong? Could all these symptoms be related to a gastrointestinal issue?