My dog had a couple small bumps under his skin, about the size of half of a pencil eraser, and i squeezed them and out of one of the this harder thig came out then a small ball of puss, i am worried and dont know what they could be, i was thinking ticks at first but i read that ticks dont burrow completely under the skin, and that they just burrow their heads. When taken out it was a light greyish colour. Does anyone have any idea what it could be?