You are not alone...Many people in this world cut themselves...Just like to feel better. But soon, the relief from cutting will be short- lived and you will end up cutting more.
Your situation does sound scary now- especially that you need stiches. Loss of blood can lead to severe problems and they can be fatal too. Please please get help. I know you feel that cuttin is your only way out as you mention but in reality you are trying to escape something else and cutting is only a way to vent. In the end, you will realize it os not worth it...Cutting is never the right way to cope. You need a better and healthier way to cope with you feelings.
Right now maybe you should ask yourself...What is causing those panic attacks? That would be a good place to start. And you say you are taking meds...Maybe you want to go back to the dr and ask him/her to refer you to a counselor or therapist.
Sorry this is so long, I hope you get the help youneed, you deserve to get it. Take care.
"everything will be all right in the end. And if it is not all right it is not the end."