Hi Faisal,
Welcome to Heathcare Magic Physician's Desk!
Your problem is too nonspecific.
There are so many causes for such a syndrome.
Try to find out if you are not stressed out due to work or house hold worries.
The next thing is you might be having
depression.
There may be some other problem like
Diabetes, blood pressure-which once found normal you said.
May be some intercurrent viral infection-
paracetamol would be a great help in that case.
Get CBC, RFT, LFT, Blood sugar and
thyroid function test and review.
Wish you a great health!