I Sat Down And My Vaines Started Poping Out Of

I sat down and my vaines started poping out of my hands extreamly bad.. I thougt they were gunna like burst or something, and now my left hand numb and on the palm of my hand between my thumb Nd point finger thefes a big blue vain that I v never seen there befor and it's looks smuged and it's like three times the size of any other vain!