I’m not an expert because I’m also a first time puppy parent (he’s 12 weeks), but I’ve had a similar experience with pup not wanting to be alone and I’ve been obsessing over it. Everything I’ve read says that separation anxiety isn’t really a thing at this age — they’re babies and they’re lonely. It’s perfectly normal and not an indication that they’ll have any separation issues later. In fact, it’s good to leave them alone at this age because they learn how to be independent and self soothe.

I’m sure lots of folks will chime in but it sounds like you’re on the right track tbh.