Everyone slips up. I know I just posted on another thread of yours a few minutes ago but I just read this one. I give a lot of advice on here and for people around me, how often do I actually follow my own advice; not enough. I'm a total mess but it helps me to try and help others. The desire to self harm is going to be stronger now and it is going to take a lot more out of you to fight it. Think of it like itching a mosquito bite for the first time that in an hour. You thought it itched before, hell no 'cause now it's on fire. The impulse to self harm works the same. You might slip up again and again and again. If you can't stop itching, slowly ease off. Work to go a few more hours, to days, to weeks and so on without self harming. I don't know if it works for everyone but it's what I had to do. Self harming is addictive, like any addiction, you have to work on the root of the problem before unwavering sobriety can even be imagined.
Best of luck. I'll be thinking about you today.