Any good method to kill a mosquito accurately?

I have been feeding a mosquito for nearly 3 weeks during that examination period. Now left last paper liao, that mosquito still wants to suck my blood! It is so small and fly so fast that I hardly have time to even have my hands in ready positions to smack that mosquito. Argg.... I have been suffering with many swellings on my legs. Stupid mosquito! Anyone have a good method to eliminate this mosquito?