I Am On Coumadin And Plavix For Cardiac Disease Sp

I am on Coumadin and plavix for cardiac disease sp multiple dvt and pe. I have developed bruises on one arm, the left, which are not caused by any specific bumping or trauma. I have often noticed a pea sized lump in the center of these bruises. It has been a problem off and on for 8-12 months. Should I be concerned?