The vast majority of my flashbacks are the nightmare-whilst-awake kind, that Hollywood is so fond of, but are fairly rare amongst people with PTSD. So that’s every sense, and all of my emotions (or none, since a lot of the time my emotions were completely turned off, back when).
Single sense are my next most common. Smelling smoke, tasting blood, feeling pain, seeing a scene (sometimes completely replacing what I see, now, sometimes sort of overlaid over the top?), etc.
My rarest ones are double/triple senses... I think, in part, because they break the 4th wall. Nightmares make sense to me, and I already lived thingA so the full immersion flashbacks are very very easy for me to “believe”, if that makes sense. Single sense flashbacks, meanwhile, often take me hours to even realize they’re happening (okay, the neighbours may be BBQ’ing but they’re certainly not BBQ’ing sewage! :facepalm: ), because very few things don’t make some kind of sense. Even if I misattribute it (like smelling smoke, and blaming the neighbours, until the penny drops). Even radio crackle/static is often lost in the beat of the city, although it stands out in the woods! ...but the double/triple etc. senses? Are too disjointed for me to mistake as something happening now, and too piecemeal to accept like a dream or memory. So they cause a kind of screeching halt. Instant-grounding, maybe.