Hi... it depends on the test that you are planning to get done... And yes, most of the test is done from the blood of the vein...Me being a diabetes since twenty years i have experienced these a lot of times.. And trust me it is not that hurting as your father might have mentioned.. With the new method that has been used and with  skilled phlebotomist(one who collects the blood) the pain due to blood collection has reduced considerably since old times...  Here the needle is injected and you will not feel more than a insect bite. The vacutainer tube is connected and it sucks the blood because of negative pressure within seconds.. Thats it.. its all over in blink of seconds unlike the old syringe method.. And do not move your limbs while the initial prick.. It only results in multiple pricks..

hey hi..stay calm nothing to worry..it will not pain very much.even if it pains it is just  temporary.even i was scared very much lol .but not now.