There should be careful monitoring of signs and symptoms of vaccine reactions for at least a week or two after vaccination. Look for symptoms like:
High fever (over 103F);
Skin redness or discoloration, swelling or hardened lump and pain at the site of the injection;   
High pitched screaming, which is shrill inconsolable crying by babies that lasts for hours  
Collapse/Shock, which is known as a hypotonic/hyporesponsive episode, when a child suddenly goes limp and may have pale skin or blue tinged lips 
Excessive sleepiness, when a child sleeps deeply for an unusually long period of time and does not wake to eat
Convulsion, also known as a seizure, which may include rolling of eyes, blank staring for long periods, twitching, trembling, shaking, stiffness and jerking of the body     
Brain inflammation, also known as encephalitis or encephalopathy, is the most serious vaccine complication. Depending upon the age, symptoms can include agitation, high-pitched screaming with arching of the back or inconsolable crying, convulsions, muscle weakness, paralysis, double vision, slurred speech, mental confusion and unconsciousness.       
Behavior Changes and Mental or Physical Regression after vaccination can be signs of brain or immune system damage, such as loss of muscle control and developmental milestones, sleep disturbances, personality changes, onset of severe allergies and intestinal disorders or other dramatic changes in health.       
If there is a question about whether or not brain inflammation or another type of serious reaction is occurring after vaccination, contact the person who administered the vaccine(s) and go to a hospital emergency room immediately.
The details of the health problems experienced after vaccination should be entered into the permanent medical record and reported to the federal Vaccine Adverse Event Reporting System. 
via Vaccine Impact Do You Know How to Recognize a Vaccine Reaction?