Bulging hand vein.. Please answer?

My left hand has this one vein tht will bulge more than all the others. It looks worse than my right hand veins! And its not even the whole vein it kinda bulges more in the middle then thins out almost like theres a lump from appearance but there is not bc it is soft.... This all started after the nurse tried to get an IV in tht vein when i was in labor.... Ever since ive noticed this vein get lots bigger than usual... It use to ache too but i havent had tht lately... Just the extreme bulge when im hot or hold my arms down which i know is normal but is the vein being like tis normal or could the IV have caused the damage?? I'm only 19 and i've never been overweight or had any health problems other than anxiety! Advice please?