I Seem To Have Developed A Boil/pimple Like Bump On

I seem to have developed a boil/pimple like bump on my buttocks that's sore to the touch there's no redness or selling around it just the bump itself what could it be ? It kind of looks like an ant bite except it's a little less as round as a dime and sticks out quite a bit I thought it could be a wart but it's squishy like its filled with pus or something but has no head