I had a tb shot 4 weeks ago and for the first 2 weeks it was barely raise and tender but it went down now it is 4 weeks later and the spot is still red about the size of a dime and a little rough what does this mean?

This doesn't mean anything. If you were going to have a reaction to the shot it would have happened within the first 24-48 hours. Since nothing happened during that period, your skin is just in the healing process.