Haha ok, well this is a bit ironic. I donate plasma. It is pretty much the same process as donating blood, but there is a machine that separates the plasma from the red blood cells and returns the RBCs to your body. Well during the return cycle, my blood clotted a bit around the needle and they had to remove the needle and finish the return in my other arm with a new needle. It seems there is a very large bruise around the punctured area of the arm it clotted in. I'm not worried about the bruise, but there is also a tiny lump in my vein that feels like scar tissue, though I'm not sure what it is. Is it possible for that lump to be a remaining piece of clotted blood? What if it makes its way up to my heart? What if I die due to donating plasma which saves lives?