I missed or blew my vein shooting meth. my arm is strikey red a little pain some swelling. keeping a heating pad firmly around my arm all day. i cant go to the hospital and my family cannot know. what should i tell i did to my arm?

This could be a serious infection of the blood vessel and/or skin around the blood vessel. This can lead to an infection of the blood as well as the heart valve which can be very serious and result in a life-threatening infection. You need to see a doctor ASAP, probably in an emergency room so that you can receive the antibiotics you need, likely IV antibiotics. Good luck to you!

Your description is almost certainly consistent with a local infection, likely an emerging cellulitis, and/or phlebitis, which can worsen rapidly in the absence of interventions. Time is of the essence. Seek care at a hospital ER or Urgent Care Center, and be transparent and honest with details to the treating physician.