I think my puppy has serious FOMO or at least I’m hoping

I have been really stressed thinking my puppy had separation anxiety but now I'm not so sure. We have only had him a week and I know he is still adjusting

However today after breakfast, a walk, and playing we put him in his pen with toys, bed and a chew so we could do some work. We were 6 feet away assembling a bed and he whined and whined and whined just sitting there not stressed at all but upset because we wouldn't let him sit next to us. This lasted less then 10 minutes and then he went to sleep.

Another example is if he can hear someone in another room even if we are with him he starts to whine and I think it's because he can't go see what's going on

I think he is like a kid and gets upset when he doesn't understand or can't get what he wants

Has anyone else seen similar behaviors and it wasn't anxiety? Did they out grow it with time and understanding?