With the grey color it sure look's like a tick engorged with blood, but not positive. I wouldnt force it, but try carefully with a toothpick or something similar to see if you can lift one end of the grey object up. If you can move it some, check to see if it has any legs. If it does, you could use tweezers to pull it out, just make sure you get close to the head of the tick (if it is a tick) and pull slowly trying to make sure the head comes out with it. A vet would also be a good idea to be on the safe side.