GC conure just sits in corner of my living room all day - please help!

Hello everyone, I need some help with my GC conure Bailey. He's 16 years old, and I've owned him since he was 8 years old. He doesn't have clipped wings and we open his cage in the morning so he has free roam throughout the lounge throughout the day. Lately he has become very territorial of a spot in the room, namely under the sofa in the corner. Its a very secluded spot and he attacks anyone who goes near it/looks under the sofa. He used to sit on the cage and tweet at the birds outside or sit on the door handle and look into the garden, or alternatively just play on his bird gym, but all he does now is sit in that corner looking puffed up and irrate. All day. If someone drops a piece of paper or something down there he might destroy that, but otherwise thats all he does, occasionally flying back to his cage to eat/drink. I am really worried! Is this a phase? Like a midlife crisis? Is there anything I can do to make him feel better? Silly as this may sound it used to be like we were best friends, but then I went to uni and he stayed home with the family. He progressively got more and more mad at me, and I understand why as his mummy isn't home a lot, but he didn't start this hiding in the corner thing until the summer, when I was home. I really don't understand. I don't want him miserable!

He may be hormonal, guarding his 'nest'. Giving him 12 hours of sleep can help hormonal birds.

I really think that you should bring him in to see the vet to rule out any sickness.

I don't want to scare you but I take him to the vet to be sure. But is does sound like he's being hormonal. Are you 100% sure he is a boy? I thought my GC was a boy until it started acting weird and a couple of days later i found an egg

I say vet visit to make sure he is ok. He could very well be hormonal. Better to make sure he is ok. The fluffed up worries me