What Causes Induration With Severe Itching And Bruising?

I have fibromyalgia, and due to working in an inpatient mental health job, I've now had 4 tb tests inside of two years. The other three came back completely negative, not even a sign of a reaction in the least. My last negative was just 3 months ago, now for a new job, I've just had another test that came back with a 7mm induration that itches like crazy and feels deeply bruised. I had a chest xray done today but no results yet. Is it possible that I was exposed and 'got' tb in such a short time, or is it likely that the hyper reactive aspect of the fibro immune system just went nuts at being tested so often in a short time span?