Wht tst should i do for tsh?and wht is norml tsh level?and wt should i do if it is below avrg?

Blood test: Tsh is a blood test to assess your thyroid function. Various labs use different techniques on different groups of people so that there can be differences in "normal". Your results should always come with apprpopriate reference range for you, eg pakistan. Always discuss your results with ordering physician who can offer you various options available in your country of residence.