Wearing Masks and CO2

@vivify said
In the link above it says:

"Carbon dioxide intoxication and carbon dioxide poisoning are independent of oxygen concentration, so you may have enough oxygen present to support life, yet still suffer from the effects of rising carbon dioxide concentration in your blood and tissues."

Do you disagree with this?

Whether that assertion is correct depends on context and only applies when the CO2 levels in the air are raised without a corresponding drop of O2 levels in the air so to make the resulting stimulated automatic breathing response fail to manage to fully compensate for both in your blood.
This is not the same as breathing in more of your own air because the air you breath out has not only more CO2 but less O2 and is such that the resulting greater breathing rate from that simultaneously and adequately compensates for the concentrations of both CO2 and O2 in your blood.
This is why breathing in some of your own breath generally has little effect on either the O2 levels or the CO2 levels in you blood providing, of course, the CO2 level in the air you breath is still not excessively high and the O2 level in the air you breath is still not excessively low.

I once read an excellent biology book, which I no longer have, that explained this aspect of the homeostasis of breathing which is why I know about it.
I tried googling to find a weblink that explains this aspect of the homeostasis of breathing but strangely so far have failed to find anything directly relevant to this but only vaguely and indirectly relevant and of no help here.

ANYONE:
Do you know of such a relevant weblink?
I tried the 'obvious' of
https://en.wikipedia.org/wiki/Homeostasis
and
https://en.wikipedia.org/wiki/Breathing
but couldn't find anything relevant in those links to exactly what I am talking about here.

@humy said
This is not the same as breathing in more of your own air because the air you breath out has not only more CO2 but less O2 and is such that the resulting greater breathing rate from that simultaneously and adequately compensates for the concentrations of both CO2 and O2 in your blood.

So then the problem is that I stated my question incorrectly. I should've asked if breathing in your breath throughout the week for a full shift can cause health problems, instead of asking about CO2. Inhaling your own breath is a different matter than how much CO2 is inhaled. It was my mistake.

Thanks so much. You've been a great help.