Thanks for posting you query to health care magic.
it is high grade 
fever  you need take care of it . 
first you should bring it to down by doing  cold sponging of body with tap water (dont use ice or icy water) and give Syrup 
Paracetamol  150 mg .
simultaneously baby should be investigated for :
1. 
Blood culture and sensitivity to microbiology lab it will suggest bacterial cause of infection and sensitive antibiotic to treat it  as you are taking antibiotic empirically.
2. Total and differential blood count.
take care of baby to not aspire vomitus inside lung to prevent 
pneumonia .
Give Domperidon paediatric syrup two times a day  to relieve  
vomiting .
if complaint increases or not releived by above measure contact immediately to health care centre.
Continue with Amoxy -clave till you get culture and sensitivity report .
review me after investigation report .
Hope you would be satisfied with my answer .  Feel free to communicate if any query .
regards,
Dr.Manish Purohit
Infectious disease specialist