Hello bluelight, I need help please! My friend ruined veins in arms, and while searching for others tried the vein on top/side of the lower arm. They registered fine, pushed down plunger, & at some point re-registered to make sure still in vein (maybe bc they felt pain?) & found that they were NOT still in vein. They pulled out and immediately a huge swell developed. They are in brutal pain with swell has gotten worse over the last 48 hours. The color of the swell is red. Is medical attention needed? How can you tell if its infected or just like a bruise that needs ice? What should they do to speed along healing?