He does sound very similar to me since I also had this kind of a busy routine pre-lockdown. I'm glad you try to understand his feeling with such patience. He's lucky to have you.
Not sure how it is with him but I may have two types of 'Dark Mood'. One where I feel down, anxious, lost, not sure what to do or where to go. The second one where I feel angry, where I can become quite bitter. In both instances, I tend to stay alone and avoid people, especially people I love, not because I don't love them anymore but because I don't want to risk hurting them. So, if he isolates himself when he's feeling down, don't take it personally. He'll always come back when he feels ready.
Meltdowns, shutdowns and anxiety attacks are different for every person, so I can't tell you how bad it is for him. Each of our situations will be different, depending on emotional state and experiences.
I rarely have meltdowns, so I can't tell you how they feel. I am more of a shutdown person and I shutdown slowly, gradually. From what I understand, this is the main difference between shutdowns and meltdowns - shutdowns seem to be directed inwards and are rather quiet, meltdowns often blow up onto surroundings. In both instances, something happens that made everything just too much.
When I get into shutdown, I may become less enthusiastic about things, quieter, seemingly more tired, with little or fake smiles, sometimes mentioning migraines or headaches. I may say that my eyes hurt, that it's loud or that things seem to be a bit too much at the moment. On the day shutdown finalises, I will withdraw early and ignore any received messages, just being with myself, most often in dark and quiet. I don't ignore people out of malice, despite what some would thing.
Anxiety and panic attacks are nasty and I hope you'll never see or experience one. My family witnessed two of mine. Both times were utterly humiliating. Maybe it would be different for you at him, you seem like a gentle person so maybe this kind of quiet, soft coaxing could help, but at the end of the day, no one wants to be seen in this kind of a vulnerable state. Also, it's messy. Kids don't look cute with drool and snot on their faces, adults are even less cute at the time.
But he may be just anxious, without any attacks, you know? So no need to get concerned over things that may not be true for him. Maybe he's just an anxious 'I'm going to walk a hole into my floor' type
. I tend to be too, but then it was already mentioned.
Oh, if he's already nervous, maybe mention that he could limit caffeine? Caffeine makes you even more nervous.
And apologies for the long message. Good luck during the quarantine, don't forget to also take care of your own health. It's a difficult time for everyone involved.
