What Causes Bulging Of Veins Leading To Pain In Arms And Legs?

I am having a few veins pop up, become enlarged as if something has cut off the circulation & then leave a bulge under my skin which usually hurts. Then after a few days it will subside. I used to have tiny veins in my feet or hands do this when hitting the skin to hard or a twist, which would hurt & sting leaving a dark purple area under the skin. Just recently I ve had a larger, deeper vein in my arm & one in my leg which hurt for days. Is this an indication Something serious is going on? Thanks, Toni