Dear Tanya N: It is difficult to say exactly why you may be having the discomfort. It could be scar tissue or, in some cases, just anatomical changes. It would be a good idea to inform your doctor the next time you see him/her. After examination, he/she may be able to shed more light on your discomfort. No, you should not have blood pressure or blood work in that arm - that is forever, unless there is a reason to change that.