Needle in finger, had to cut finger off.?

I was playing in my hideout with friends when I put my finger on a needle, it looked like a needle they use in hospital. My friend said I would get aids like those children on tele for children in need. He said I had to cut my finger off to stop it, so I chopped it off with a wood axe. My friend then put fire on it to stop bleeding. My finger is now swollen and black. I don't want to tell anyone cos I'm scared.