I suspect pets can detect changes in odour or behaviour in their owners as their universe relies on such cues far more than we do. Dogs, being social and far more trainable, are suited as detection devices and have been shown to sniff out all sorts of things. Although there’s rumours of a successful study where cats are able to detect stressed out people who have eaten tuna sandwiches…
Even ppl can sniff it out smells like butric acid and it's not removable from clothes.
I can smell it on me when I eat the wrong things.
When the smell sets in I've got about two days before mental breakdowns and paranoia.
My dog acts weird when I'm on acid even if I leave her alone. It is a stress of sorts, I suppose.
tl;dr: humans produce a different odour when under pressure – and dogs can sniff it out