IMHO I think at the moment the best thing you can do is try and stop worrying. I say this as a mother to a DS (9) with AS, a DS (5) with HFA and an NT DS(3). It is too early really at that age to know if your DS has autism or not, and I would think that your anxiety will be affecting his behaviour as he will pick up on it.
The problem is, is that the MCHAT test to pick up autism is designed to be used from 18months. Think how much development a child goes through between 10months and 14months and then how much more there will be between 14months and 18months.
I can safely say at age 5 and 9 my children (who are both very high functioning) do not wave. Although DS2 does have to have a hug and a kiss when I leave as part of a ritual, he doesn't get why his younger brother might want to wave goodbye.
DS2 didn't recognise his name at 12months, he didn't point at 18months (with anything hand or finger), even now when he points he won't look to check that I am looking at what he is pointing at (I have just taught DS1 aged 9 to do that!). DS3 does it naturally.
DS2 adores hugs and cuddles - he is very touch sensitive and he needs the firm feeling. However he still now at 5 throws himself at people he doesn't know trying to get hugs from them.
All of their facial expressions for social use are learnt behaviour. e.g. DS1 knows that if someone smiles at you, you should smile back. But equally he thinks that means that if someone is hurt and crying you just need to smile at them and they will be fine as the rule is they have to smile back. How is your DS at empathy? Might be a bit young yet, can't remember when DS3 started showing empathy. But the older 2 if someone is crying are quite likely to either start screaming at them to shut up as they are hurting their ears, or ignore them completely. DS3 would come and give someone crying a hug and ask what is wrong.
DS2 until he was quite old (maybe 3) would get very cross if I tried to get involved with anything he was doing. I used to feel a terrible parent just sat on the sofa watching him, but he threw a tantrum if I disturbed him. When he was a baby he used to throw tantrums if I changed his nappy - I have never seen a small baby go purple in the face throwing a tantrum in the way he did when he had to be changed as it was changing his routine.
On the plus side, DS2 is doing exceedingly well in school and is considered G&T there. They genuinely can't believe he didn't speak until well after his second birthday, and no 2 word phrases until after his 3rd. So even if your DS does have autism it genuinely isn't the end of the world - he is definitely more advanced at 14months than DS2 was.
At 18months if you are still concerned get a referal to a paediatrician, but even then you are unlikely to get a dx for several years as often developmental delay and ASD can appear similar at a young age.
Take care of yourself and please stop worrying for both yours and your DSs sake.