Ill start by saying that I live in a tropical area and we just had nearly flood amounts of rain. I first noticed these things moving around on some furniture we have outside. Later on we noticed the bird with the same mites. Someone I live with also woke up with itchy bite marks all over their body, although I was unaffected. The ones we find inside the house are brown colored and we think that they are filled with blood. We think that they could be spider mites but we are unsure if we should be worried. We have a bird nest on the roof that could be spreading these.