My 10 month old ds isnt crawling/bum shuffling, he can sit up for long periods but all of a sudden will just throw himself back so have to sit with him ready to catch, he can roll and slide backwards on his tummy pushing himself with his arms to get to things when he really wants ,no first words or babbling as such more cooing noises,he doesn't pull himself up either not even in his cot.I'm get really concerned as it's not just one thing he seems to be behind on. Should I make a doctor/ health visitor appointment Or is he too young for them to be concerned? Any advice or reassurance please