hard limp on left collarbone

   About 5 months ago had pain and stiffness that moved from right shoulder across back and my neck making its way to the left shoulder eventually.(ABOUT 6 MONTHS EARLIER I PUT IN A (HEAVY) STONE WALK BY MYSELF) Now, 3 months later, no stiffness or pain but head and neck is very itchy. I take Benadryle for the itching. jUST AT THE BEGINNING OF TESTS FOR WHY THIS HAS HAPPENED. What happened to you?

 I have a bone hard lump on my left collarbone, it does not hurt. I have had it for about 2 months, about 6 months earlier I put in a heavy stone walk by myself, a few months later I had pain and stiffness that moved from my right shoulder across my back and neck to the left shoulder. this went on for 6 weeks, now no pain just a little twinge of pain in right shoulder, but head and neck down my upper back is very itchy. I take benadryl. I am in the early stages of testing, any suggestions?