My DS who is 18 months old started shaking his head from side to side when he was maybe 8 months old and we thought nothing of it but over time we have started noticing other things. He constantly moves, he can't stand still, if he stays in the same spot he has to run on the spot, usually on his tip toes. He doesn't play with toys the way that they are intended, he tends to hold them and run about with them. With jigsaw pieces he does not attempt to put them in the holes, instead he enjoys putting them in a box and then out of a box and continues this for some time. He also enjoys going into his drawer full of clothes and taking them all out and then back in again and does this continuously for at least half an hour. His head shaking is more often than ever and is frantic, my DH and I are often worried that shaking it as frantically as he does could even injure him. He often fidgets with his hands, in a flickering manner. Even at bathing he has to lie down and splash the entire time whilst dipping his head in the water.
There are things that seem to contradict autism however such as he babbles (no words yet) and gives eye contact to people close to him, however if strangers come near him he puts his head down and covers his ears with his hands, he also does this in loud, busy or new places.
He has also had a few meltdowns where nothing calms him down but time and patience.
I am so confused so any advice would be appreciated.