An extract from Brian M. Sammons and my short story in Cthulhu Unbound 2 follows:
Harrison Peel woke awkwardly, worried that he sensed ripples of déjà vu. The dirty hotel room with giant bugs scampering on the ceiling remained familiar, and the air sweating like an exerted fat man in this tropical heat was as oppressive as the moment before he drifted into sleep. It was his body clock was worried him. He felt as if it were late afternoon even though his watch said early morning. Had his watch failed? Had he slept all day and not noticed?
Sitting up brought stomach acid to his throat. Then he gagged. The nausea so bad he hoped only to vomit. Several moments of retching brought up nothing, and still the nausea would not abate. To counter the acid, he drank sterile water from his canteen. He choked on that too, vomited it up as he did.
Out of bed, peering into the broken mirror, Peel saw a haggard man. He saw himself as if he were a terminally ill cancer patient. Not the self-image he had witnessed in the same mirror yesterday when he had felt good and fighting fit. What had happened to him? It terrified him that he did not know.
It was then glancing over his shoulder that he noticed the tall gangly man.
Without hesitation Peel spun his whole body, pinned the intruder against a wall. One hand locked an arm so it would be a painful exercise to resist, the other pressed against the windpipe so he could kill without effort.
"If I die, Major," the stranger gasped, "so do you."