There are two tiny pink spiders that live in houses. This one is the Pink Prowler,
named after its colour and the way it walks with its front legs.
They are tiny, 1.5-2mm long (head/body), and usually nocturnal, hiding in the day. They are native to most of Europe.
This one is even smaller and may also be a pink prowler? It doesn't have the dark red body of the ones above.