give her 2-3 days time and see. if she still runs fever or has decreased appetite and not wanting to walk or play then visit your pediatrician

Greetings It is common for toddlers to refuse to walk after an 18-month DPT booster, as the thigh injection often causes significant local muscle soreness and swelling. These symptoms, along with a mild fever and decreased appetite, are typical vaccine responses that usually resolve within 24 to 48 hours. You can help by continuing the prescribed paracetamol for pain and fever, and using a cool, wet cloth if she resists an ice pack. Contact her doctor if she experiences a high fever over 104°F, inconsolable crying for over three hours, or if her leg pain doesn't improve after three days. Always double-check medication labels to ensure the correct dosage and follow your doctor's specific instructions.

Very common after DPT booster. (Especially whole cell vaccine) It’s due to pain at injection site, not paralysis. Child may refuse to walk for 1–3 days, appetite ↓, mild fever – all expected. Give paracetamol regularly (not only for fever) for 1–2 days. Don’t force walking. Should improve in 2–3 days. Show doctor if: • no improvement after 3 days • swelling/redness increasing • child not moving leg at all even when distracted • fever >2–3 days

Visit physically to nearby pediatrician.

That's is common side effects of DPT vaccine it normal only The pain and fever will go by 3 days Till than you can paracetamol

Consult with Pediatrician physically for further evaluation and treatment