I have a strange painful grape-sized lump in my left buttock. It seems fluid filled, but pressure doesn t pop it and I m not partial to draining it otherwise. It s not very close to the anus , but it s still on the cheek. The skin there is slightly darker than the rest of my skin. It s very bothersome. I m pregnant and considered possibly hemroiding, but only in the first trimester. What could it be?