What Causes Cold,fever And Headache?

i was having fever,cold, cough & little bit of weakness on monday, so on the same day i went to doctor, he provided some & next day i was feeling. then in next to day i got shivering fever , cold, cough, headache & weakness so again on the same day i went see a doctor he provided e antibotic medicine & he told to see that after 48hrs if i get fever i would have to do a blood test.

as request u to clear my doubts that as per my symptoms what diease i may me having is it a normal cold , cough fever or should do a blood test clarify my unwellness