your symptoms are descriptive of what we call as obstructive sleep apnea.
Check whether you are snoring
from your family members as you may not be aware of.
You are overweight and it contributes to the above.
This condition disturbs sleep at night and hence you feel heaviness in head after waking up and feel sleepy in the working hours.
start doing regular walking
hemogram and TSH and sugars check your blood pressure
all these are must
finally for confirmation you need
sleep study (poly
which confirms your problem.
With positive attitude you get these tests and I will guide accordingly.