My boyfriend had an IV drip set up on his left hand at home, and I was left to administer another set of antibiotics through it. (I m not a trained nurse or doctor) as we went to do it we forgot to screw on the white cap on the top of the attachment in his hand. I turned the drip on and nothing was dripping but my boyfriend got severe pain. We realised the cap was off, then tried again. It started dripping down the line but still he had a lot of pain so we didn t continue with it. A week later he now has a small painful lump in his forearm and bad pain up the arm. I m scared its an air bubble or collapsed vein!? Should we be worried or will it go away?!:/