I got a chemical on me and I went to the doctors and I need help!?

I got a chemical(Iodine- & AgNO3 or Br- & AgNO3 or Cl- & AgNO3) on me more than a month ago at school. I went to the doctors and they said everything was fine. my hand stopped burning and everything but my skin on the left hand became thinner I guess and can feel more of something when I touched things. I went to the doctor again this past monday because my hand was feeling burnings like small bites. They said it might be stress and said to go to a followup on Monday. The small bites stopped but I felt needle pain in my 3rd finger and other places. Then my joints and other places seemingly on the bones are soring and hurting at times. I'm itching and it feels like my hand is drying. Help on what's happening please!