How do I know if the result..

I got the TB skin test done yesterday morning and tomorrow I have to go in for the results, but I'm kind of worried because today when I woke up I had a small reddish purple spot (about the size of a pencil eraser or pinky fingernail) on the site of the injection. I don't know if this is bad or not. The last time I had a TB test was maybe 7 years ago and I didn't have anything on my arm but this time I do. Anyone have any idea if this is bad or if it's normal? Obviously I'm going in tomorrow for the results but I want more info before I go in. Thanks!

If will be red and raised and bumpy if it is positive. Your's does NOT sounds positive but since I can't see it it is hard to say for sure.

when nothing happens to the place where you got the shot.

Why would you want more info when you go in. The doctors and nurses know all you need to know and will share it with you. Chances are that you are negative, so no worries. If you are positive, they then will educate you on the treatment plan. Interesting that you would want information up front on something like this, as to how to read it. Are you interested in being a nurse or a doctor? Or just curious about health matters? Have a great reading...