idk if you have taken the SN already but if you regret it you should probably call 911 and get yourself to the hospital. I'm not sure how much you have taken and depending on how much you are likely to pass out between the next 10 to 30ish minutes. Methylene blue (the antidote) is usually effective within the hour you have taken the SN. And you can always reconsider if you have regrets - nothing needs to be done immediately.