I have been sick what do i have?

ok i have been sick since last friday night,i started getting sick friday evening with a mild sore throat on my right side, then it turned worse saturday and then sunday i started getting chest discomfort, then monday night it turned worse i would rate the pain at least a 9 and a half i was freezing and dizzy and just didn't feel good, then i went to the doctor on tuesday and felt a little better, last night i started feeling bad again and today it feels like i have no energy and i just feel run down, i have a little cough and the doctor said i was starting to get an upper respiratory infection and he put me on an antibiotic before i get bronchitis, but now i have a stomach ache,earache, and a headache please help do i need to just go to the ER or what??