Hi. first of all u need not to be worried at all as you have mentioned that, x rays, ecg, holter and stress echo reports are all normal, so one can easily rule out a heart disease
. The episodes of fainting sensation and light headedness can be due to ear problem also, for example a condition kown as benign positional vertigo or some other ear ilness. You need to consult an ENT specialist
for that. Also you should undergo an xray of neck to rule out cervical spondylosis
as it can also lead to faintness. Your fatigue may be related to uncontrolled diabetes
. A thyroid function test may be necessary as hypothyroidism
also leads to fatigue. Lastly very uncomonly a lliver function test may be required.