Puppy hates being alone in crate

Hi all! I have a 12.5-week-old Mini American Shepherd who’s been home for a week. He’s fairly potty trained (only one accident) and sleeps great in his covered crate by my bed—sometimes all fours up!

But during the day, when I crate him alone for naps (max 2 hrs), he whines/barks for ~15 mins before settling for varying amounts of time (depending on whether or not he actually naps, max 1 to 1.5 hour, but sometimes as little as 10mins) and then resumes barking/whining. I’ve tried putting in Kongs and toys, but he won’t touch them unless I’m around. I also make sure to only approach the crate once he’s quiet.

I’m worried it might be early separation anxiety. He eats all his meals in the crate and doesn’t seem to dislike it at night, but I’d love for him to see it as his space and go in on his own.

I just got a second crate for my study and plan to use it for daytime naps instead of the bedroom one. Any other tips?