Acidity, throat burning, sleepless ness, constipation, burping, flatulance, weakness etc. : PLEASE HELP

Dear All;

I am 40 male. About 3 year I started having symptoms of hyper acidity and reflux to which I ignored, till it ended up in severe weakness and sleeping problems. I could not really stand and have no urge to eat. I was in pantocid for sometime, felt better and followed the message board here and took some doses of Zinc. met. by which my leg weakness diappeared with some other symtoms, but the acid reflux did not go. It disappeared for some time with food control and again truned on since last one month.

My smptoms are: burning sensation in the throat when I am hungry and the sensation disappears on eating, but appears again after the meal. It used to be very severe in nights, at around 1-2 AM I could not sleep and only after taking some antacids I could sleep for sometime. Lately, I developed shivering after dinner and during the nights which used to awake me up.During this time, I used to pass stool in the midnight (after waking up) and take some antacid, feel a bit better and try to sleep. My doctor advised me to take Metronidazole for 7 days (suspecting for giardia infection). It worked nice for me, atleast many of the symptoms (night wake up etc.) were gone, but since metronidazole causes heper acidity, my acid conditions improved a lot. Due to which I feel more burning sensation in the throat and metalic taste in the mouth after a meal.

I again followed the message board here and took Nat Phos. 6X (4 tab, 3 times a day)for 1 week. It worked for me like miracle. Most of the symtoms were gone and I used to have a good night sleep But, during this course, suddenly the symtoms reappeared. I stopped Nat. Phos.I suspected of a giardia infection again and took a single done of China 200. I am not sure if it worked at all, and since last night started Nat. Phos. again. My symptoms are also severe in the afternoon (4 to 8 pm).

Now could anyone help me out to suggest a proper diagnosis and remedy? I will be really thankful for each of your valuable suggestions.