i just started taking erythromycin because of what the doctor cal...

i just started taking erythromycin because of what the doctor called an infection...she said the infection is what caused my miscarriage...i went to bed with extreme pain in my back..i thought nothing of it except standing too much maybe so i went to bed thinking it would be better....i woke up with severe pain in my upper abdominal area...when i breath in it pains me....my neck is killing me and i am sore to the slightest touch...dizzy spells, drumming headaches, i cant seem to eat...i noticed my appetite has been going down..i need to take this but i may stop if after today the apin is worse