The doc will tell you to give tylenol before shots. . however i NEVER did. i dont give meds unless its nessicary. shots will likely leave little knots on their legs and thats ok. if they act like it hurts put cold compress on the injection area.
My dd ALWAYS gets a fever with her shots so I give her tylonal before we leave and she usually needs it through the next day and she's cuddly and sleeps. Never had any issues (bumps, rashes, reactions, etc)