Hello and thank you for posting your medical question on E health forum.
From the history provided, it seems that your symptoms of light headedness and weakness could be stress or psychologically induced, since most of the investigations and blood tests have been normal.
You can take some break for a few days from your regular routine, and take some rest. This might be helpful to reduce your stress.
The other reason of your dizziness, could be a benign positional vertigo, which can be helped by intake of OTC antihistamine medications. (Dramamine).
Other conditions like GERD or acidity that present as chest pain can be helped by taking antacids and prilosec.
I hope this helps.