covid can have an affect on the central nervous system. (no smell, for example)
Having a brush with death can have a mental health affect.
Long term fatigue, especially when it seems like you're the only one, or you wonder if your fatigue is real, can be very frustrating.
If anyone here is knowledgable on the havoc wrecked by the Spanish Flu, you'll know that beyond a % of survivors developing schizophrenia, and beyond the fact that babies born to surviving mothers were shorter and weaker than those born earlier, later, and to non-infected mothers, there were also many cases where patients developed CFS/ME.
Regarding those who are edgy- it's been documented that Woodrow Wilson was increasingly irritable and edgy after his brush with the flu (although he suffered a stroke as a result of the flu so I'm not sure I'd blame the flu- I'd rather blame the stroke).
At this point we can still blame quarantine, but as more time passes we'll have to start considering the possibility that yes, it's possible some of us have developed chronic illnesses/conditions that are here to stay.
Since there's been some talk up thread about how few of you know people personally who have lingering (hopefully not long-term) effects:
My parents both claim that they've not regained their strength and tire easier than before.
I myself, who had a borderline serious case (oxegyn was in the 86-90 zone for a few days but I managed to stay out of the hospital) have noticed a definite change. Walking up a flight of stairs now means taking a rest. I will point out that it's been harder to work out due to restrictions, and it might be an effect of me being more sedentary than usual, but I've also never been out of breath when climbing a flight of stairs, regardless of my current workout schedule. I'm not ready to draw conclusions at this point, although I do plan to request a chest xray at my next annual checkup to confirm that there's been no damage (there are a few more symptoms I've noticed so I'm pretty sure my doctor won't deny my request).