Dr. Hanif warmly Welcomes you! Thanks for consulting at my virtual clinic. I have carefully worked through your case, and I can realize your health worries. Being your physician, I assure you not to worry as I will take care all of your medical concerns.   Don t worry please. What happens is, sometimes due to slip of needle out of the vein causes blood leakage underneath the skin and it causes bluish discoloration of the skin. That color is actually of the blood that have leaked from the vein from the needle puncture site. What you to do is apply warm compresses and take Ibuprofen. It will automatically dissolve that blood and in a couple of days swelling will also subside. Hope I answered all of your health concerns . If you have further questions in future, feel free to contact me anytime. In the start of your question write my name, and I will get back to you in no time. If satisfied, please click you found it helpful. Have a wonderful time ahead.   Best Regards! DR. MUHAMMAD M. HANIF USA