I use meth in an IV the other day. The needle was new & never used, blood registered in the syringe when I pulled the plunger back. I stopped when I felt stinging and checked to make sure I was in the vein, and I was. Very mild stinging continued for the last 7 to 8 units of the shot. When no knot came up I thought it would be fine. Four days later, I have a knot that grew from the size of a dime this morning to a half dollar and its very painful. I am hoping for a home remedy. I have soaked in hot water tonight, but it feels like its getting worse by the minute.