Hi im Dr Fahim and i will help you with your query . . . Its seems that yours wife has a problem with a blood coagulation if there is a swelling at blood drawing site. I would like to ask why the blood was taken out and it was venous not arterial prick. Hard swelling and if expanding + very painful, suggest arterial bleed. There is also history of easy bruisability, which hint towards blood coagulation problems. For time being you can apply ice followed by pressure bandage. I would also like to know any drug history of her, any medication if she is taking in past or right now. I would recommend to see a doctor who might advice lab test ie blood complete picture, bleeding time, PT , aPTT to assess coagulation profile along with appropriate history and examination to reach a diagnosis. Wishing your wife a rapid recovery, and do rate my answer if find it helpful Regards