What To Do For The Spots In The Body Due To Bites?

Hello. I've been getting all this bites on the side of my torso and on my left butt area for about a month now. It seems like I am getting bitten on the same area everyday. The bites first get red and filled with small pimple like puss in the center. The bites then leave brown spots . I have no idea what kind of bugs are biting. The sometimes itch but the itching is not that bad and they do not hurt. Please help . The spots from these bug bites are awful