I feel drowsiness all day long and am not able to concentrate

[inwinder]

I have a serious problem since more than an year now which I have no solution of. I have gone to neurosurgeon, psychiatrist, ent, etc. I feel drowsiness all day long and am not able to concentrate. Below are the symptoms I have followed by the tests I had done including blood test and mri.

Symptoms:
Day long Drowsiness - standing, sitting, walking, driving
Fatigue
Lack of concentration
Memory loss
A little speech problem (rare)
Sleepy during driving
Blurred vision
Reading and Writing problen
Headache mainly on both sides of the head nerve pain
Understanding things take time
Loss of appetite
Focus lock
Not refreshed after sleep even after 10hr
End of the work shift after 8 hrs, i am totally exhausted.
Ringing noise in left ear

Test done:
MRI of the brain and nerve - all clear
Front sinuses MRI - all clear
Neck xray - clear
Blood test - all fine, hemoglobin 14.7, vitamin b12, b5 at good level, tsh 1.75, iron in level
Psychoanalysis done - a litte OCD but nothing harmful.
Ear ent checkup -  all clear
Eye sight test were ok have normal vision.

Current medication:
Anti depressant - 3months no effect

My body:
Height:6ft 1in
Weight: 73kg
No feeling of sadness
Fatigue 24x7
I dont snore while sleep and mostly sleeps are plesant.
Modafinil or substitutes increases my heart rate and anxiety.
Duvanta 40mg (Duloxetine) was prescribed but it worsen my sleep issue and had more drowsiness than before.

Strange fact:
If i am feeling sleepy any point of the day or night and lay down on the bed with my eyes open, the high sleepy sensation subsides with in hour or two and feel a little comfortable.