I'm A 15 Year Old Girl , I Been Having

I'm a 15 year old girl , I been having pain in my right arm in the middle where it bends when I touch it , it kinda hurts and when I bend my arm I feel like a ball inside the pain comes and goes I have no discoloration please help me ! I been so stressed out about it that I cried please or can you give me any treatment to make it go away ? Also my parents have this cream for the bones and when I put it on it stops but the pain comes back