I need to ask few more questions before answering your query. Early consultations can prevent complications. Kindly contact me on whatsapp chat  (84960595 six five) Dr Faisal Zoheb MBBS , MD PAEDIATRICS , PGPN (BOSTON), FELLOWSHIP IN NEONATOLOGY ( Newborn and vaccination specialist )

Nasal block and Improper burping may causing repeated regurgitation in your child.. usually curdy regurgitation of feeds is normal in that age group..give proper burping and use Saline nasal drops before feeds to clear nasal block.. if the baby is dull,not acceping feeds well consult your Pediatrician near by

I totally understand your concern. Before suggesting treatment, I would like to ask a few questions to ensure the correct management can be provided. Contact me on Practo or WhatsApp chat. Contact number: 97012307 two nine Dr. G. Avinash MBBS, MD (Pediatrics) Fellowship in Neonatology

Greetings Vomiting curdled milk in a 3.5-month-old infant is often a normal sign that milk has mixed with stomach acid during digestion, but when combined with a cough, cold, and nasal congestion, it may be caused by swallowing excess mucus, a viral respiratory infection, or gastroesophageal reflux. Additionally, putting hands in the mouth is a common developmental milestone called mouthing, used for sensory exploration or self-soothing, but in this context, it could also suggest discomfort from teething or a mild fever. Potential causes for these symptoms include a common cold, a lingering gastrointestinal infection, or a milk protein allergy. You should monitor for signs of dehydration, high fever, or difficulty breathing and consult a pediatrician to confirm the cause and discuss treatments

Nasal congestion and cough are main reasons

For your baby ,detailed examination is needed . Consult the local pediatrician . Meanwhile ,Do proper burping  after each feed and use nasoclear nasal drops .

Consult with Pediatrician physically for further evaluation and treatment

Looks like reflux with cold. Milk curd vomiting is common. Give small frequent feeds, burp well, keep baby upright after feeds. Use nasal drops for cold. No major concern unless vomiting becomes forceful or baby is dull.

For cough and cold - Put  Nasoclear nasal drops 2drops in both nostrils every 6th hourly for 3 days For Vomitings - Give Domstal drops 0.3ml morning afternoon night before 30mins to feed for 5 days