After I heard the rumor that some bad people with HIV used needle to poke others after poking themselves, I become quite worried about it. And a few days ago I felt a sudden pain on shank when walking by a bush, without touching anything. Then I worry if there are some one hiding in the bushes and use needle with virus to poke me...However I did not find blood on skin after I came home...And did not find sore places when I examine it...