Under stressful events the mind can play tricks on you.
I think this was the case here, but as far as Pheromones or/and Psionic's i think that yes the Xenomorph could use either or both for a number of purposes.
Includes communication and maybe determination of what kind of Embryo a Eggs Face Huger would yield... but these Pheromones or/and Psionic's could be given off by the Architecture of the Xenomorph Hives.