Have your dr check you for Lime disease .good luck.
Hey I'm a 22-year-old female and I have been having not EXACTLY the same, but extremely similar symptoms. It started the same way too...I had a terrible flu like thing that seemed last about a month off and on. Now, I keep having what you refer to as episodes, and I never really feel 100%. One main difference I should point out is that for every time you say you've vomited, mine has been coming out the other end, although I'm not sure how weird that is, since I've never really been much of a puker. But I have the exact same thing with the random, weird nausea feeling and the stomach spasms. Also the jittery leg thing happens whenever I have a bad episode.
I know it's been a while since you posted this and I was hoping that if you see this, you could tell me how you're doing now... Any change? Any legit diagnosis?
My doctors have run the same tests as yours, only not the GI series (yet) and have also come up with nothing. Apparently, I'm a perfectly healthy 22 year old. Doesn't feel that way!
One thing I can suggest that you may not have considered is seeing a therapist. I know it sounds unnecessary and probably unrelated, and in your case, it might be, but I saw a shrink earlier this week for the first time and I've already noticed a small difference in how I feel. Anxiety is apparently a huge factor in why I feel this way. Truthfully, many people in my family have IBS, and it's likely I am developing it now, but dealing with the anxiety that comes along with it might change how your episodes go, it has for me. The leg trembling is likely related to anxiety, and if you ever get the sweaty palms or any tingling in your fingers or around your mouth, that's caused by hyperventilation, caused by anxiety. I had the latter when my flu symptoms were at their worst.
Any of this helpful at all?
I should also add that I never have heartburn so the reflux diagnoses seems a little odd. I've also had an outbreak of cavities (possibly reflux related?)