Hi I Woke Up The Other Day And Felt A

Hi I woke up the other day and felt a slight bruising near the top of my right inside bottom cheek. Thought nothing of it then it got worse so I felt round there and felt a hard lump the size of a marble. Being the type of person I am I panicked and tried to pop it thinking it a large spot. A bit of pus came out then nothing and it got so painful all around the area... I tried again today and just a bit more pus not a lot then blood so I stopped. It still there still hard and painful and feels bruised around the area. It's bugging me as I feel it when I sit down and walk. What could it be ?