Crate regression at 15 months

Hey everyone! Im in need of some advice because I’m starting to lose my mind. I have a 15 month old moyen poodle, he’s been crate trained from day one. He sleeps fine at night, he is an awesome sleeper to be honest. He even sleeps in a different room than us and we can leave him home in the crate for a few hours and he’s just fine( it took us a long time to get here but I couldn’t be happier with him). It is important to mention that he has 2 crates, one is a plastic one, he loves that a lot, I think it gives him a more enclosed feeling, we leave him in that when we leave him during the day. He also has a wooden one we use for the nights and that is his “everyday crate” (we use both because we couldn’t transfer from leaving him home in the plastic one to leaving home in the wooden one but it’s in progress.). the wooden one is bigger but more open.

Now for the past 3 nights he’s been awful in the crate, he’s been whining and stress breathing, sometimes clawing at the door. He doesn’t need to potty that’s for sure so I can’t imagine why this happens. He’s always been amazing in the crate, we only had a few nights where he was whining and that was mostly because of a weather front – he’s quite sensitive to those. But this seems different, he really can’t calm himself only after hours of whining on and off. Tonight I put him in his plastic crate and he is doing just fine.

So my question is, what should I do? Is it something that’s usual for a teenager puppy, is it like an adolescent regression stuff, should I let him sleep in the plastic crate for a few nights so he can learn once again that the crate is a nice place? Or should I be worried? As far as I know nothing’s changed in our routine and there was nothing that scared him when in the crate.

For some clarity: we don’t want to keep the plastic crate as an everyday crate for him, it is not big enough for that in my opinion. We are planning to buy some sort of fabric to cover the wooden crate so he can have a more den-like feeling, it’s a custom made crate so we have to sew the cover for ourselves and haven’t had the time to do it. He will stay crated because I believe that’s what’s the safest for him.

Thank you for every comment and advice! An exhausted puppy parent