Insect????

I have found little hard worm like "poo" in my front hall - which has lino in it. I live in a new house with no pets - but there is obviously something that has taken up residence in my hall!! Does anyone know what it is and what I can do to get rid of it - I only have one rug in the hall which I have lifted and have bleached the lino and the skirtings - but still the poo appears - I haven't seen anything so think it must be nocturnal. Arghhh help its driving me insane - I have visions of this infestation of insects eating my house!