I have this red little ball like lump near my buttocks and it looks like its filled with blood, and i don't know what it is and i'm scared if it's bad?

Skin infection?: Probably an infected hair or infected insect bite. Apply warm compresses and antibiotic ointment such as Bacitracin for a couple of days. If it gets bigger or does not seem to be healing, see a doctor and have it checked. Good luck!

The only: way to know is to see a doctor, examining the lesion is the most important part of diagnosis but if I want to take a guess I would say you have an infected Pilonidal cyst which is a pile of ingrown hair.