Hi can u attach pic of the tongue please
Sometimes infants can develop oral thrush(fungal infection) which presents as white curdy precipitate over tongue
If lesion looks like that u can use candid mouth paint
Which needs to be applied daily 3 times per day for 1 week
Next Steps
The same should be applied to ur nipples to prevent reinfection if any
Health Tips
Cleaning of the tongue should de done very gently with moist cloth any other harsh methods can lead to cracked tongue