lame another bruise- is it me, needle, or nurse?

Open all ears please! I know a lot of you have had blood "stolen" okay, okay taken and i'm just wondering if you have any idea as to what makes you bruise if you do. I would seriously like to know if I can prevent it for the future. I want to say that it's the nurse- lady who stated herself and I quote, "I'm very impatient!" Not what the patient wants to hear right before you jabbed them in the vein. OW!!!! So to those of you who are seeing your doctors soon or are in that particular field, can you inform me please. Cuz it hurts- like 2" by 1".