I Have A Mosquito Bite And I Was Using A

i have a mosquito bite and i was using a nail clipper and accidentally clipped some part of the skin off and now the bite has a really swollen round yellowish ball with the wounded part in the center. Its not bleeding however i can feel and see it throbbing. Like when i feel it throb i can see the blood moving in toward the wound part in the center and then moves back out. What is happening why is blood movement responding to the throbbing?