This morning, I found a small tick on the back of my knee. There was lots of blood there and I mistakenly pulled the tick off my skin before I realized what it was. Now there is a big red bruise on the vein spot where it bit me and I have burning on the back of my leg. The entire area behind my knee hurts a lot. I have washed off the area with soap, but not sure what to do now. I'm very worried.