Baby talk

My little one will be 5 months on the 10th. I feel like he’s doing great, he sleeps well, has rolled from front to back and back to front. He’s trying to crawl and he eats well etc etc

He used to coo at us non-stop. A lot of ahh’s and ooh’s but he doesn’t do it at all anymore and instead just makes a whining sound almost all the time (unless smiling or laughing). He’s been doing it for at least three weeks now. It sort of sounds like he’s in pain but then he will often smile so I think it’s just how he’s communicating now? I’m worried he’s stopped making the other sounds and he’s not using any consonant-vowl sounds.

Is this normal? What sounds are your 5 month olds making? Have the also been through this whining phase?