Fever for 7 days should be investigated.Infection should not be present.
Commonest cause is viral fever
.It will take sometime to subside.If it is accompanied by cold and cough,i prescribe antibiotic along with anti histamines
I prescribe antispasmodic for stomach cramps
.Because of medicines,you might have got stomach crampsTiredness
,headache are due to fever.
You should to hospital and get investigaed and clinically examined.
Wish you speedy recovery