my daughter is 5 month 19 days old....she rolled over from back to tummy at 3 month 10 days old and raised her head well...now she is form tummy to back....and moving forward and reaching toys...but in sitting position turning from side to side ....her head is bit shaky..... when her head get full stable..... ?when to see doctor still like that aft 6 month?or this is normal?