I found this bug crawling on my son’s skin. At first, I thought it was a hard tick, but on closer examination, I’m sure it’s not. I also wondered if it was a bedbug, but I’m pretty sure it’s not one of those either, as they look to be redder and more glossy than this - it was grey-brown, dull, slow-moving and about 3mm long. I’m in England.
It looks like a wood tick to me. Usually get them from areas where there’s a lot of pine like you would see at higher elevations in the mountainous areas. I live in Seattle and we have none, but on the east side of the Cascades, which has very dry heat in the summer you get them a lot. Nasty bugs that bight into you and burrow and suck blood. They lock in somehow and if you pull them out they tear leaving part of them in you which can get infected. You have to use a special medicine or turpentine to drive them out.
Also, I could be entirely mistaken about it being a tick.
That looks a pretty close match- and my impression was that it was a true bug rather than a beetle. It wasn’t quite as leggy as the immature stink bugs in that picture, but we have lots of other true bug species here - Googling around, I think it’s almost certainly a nymph of one of our shield bugs - maybe this one.