20 month old behind on talking? Austism?

I have had my son screened and he is about to start early intervention for speech therapy. He just isn’t saying that many words. He can say mama, sometimes will say dog or say cat, and says dada but that’s it. He also doesn’t respond to his name and he can’t follow simple commands yet. Most of the time I feel like he doesn’t even hear us talking to him.

This is worrying me and I’m afraid he is on the autism spectrum. However, his pediatrician and when I had him screened both said they didn’t think he had autism and he is just behind on speech/ language.

He excels in any physical or motor skill and is way above other kids his age. He cannot stop moving and playing. He also is so happy and enjoys playing with other kids, wants interaction with other people, and will take your hand and literally lead you to what he wants to show you.

It’s almost like his form of communication is leading and physically putting your hand on something to show you what he wants (for example if he wants something on the counter, he takes your hand, leads you to the counter, makes a gesture to be picked up, then puts your hand on the object he wants). He is very smart and very into how things move and work and what he can do. He is learning so much physically, but not much verbally.

We had his hearing checked and everything was fine. I’m wondering if he just has found another form of communication instead of using words?

We have been told he is just prioritizing motor skills over language skills but the fact he doesn’t respond to his name and pretty much ignores you when talking to him makes me nervous. If you’re playing with him, he is all about listening to you and paying attention to you, but if he is interested in something else its like he doesn’t even hear you or is ignoring because he is focused on the other thing he wants to do.

It’s almost like he has selective hearing.

Really the only indicators I am worried about is not responding to his name, saying new words and following simple commands.

Has anyone else dealt with those red flags in their toddler and their toddler caught up/ not been on the spectrum?

I’m just so worried my son has autism and our pediatrician and early intervention might be overlooking it.