I started cutting... what should I do?

So yesterday I was really really depressed and too make things worse I got into a fight with my boyfriend... so for the first time in my life I started cutting. It wasn't really like the hardcore people who get a big knife and slice up their arms... i was just I bed, I realised I was sitting on a pin lol... so I just started cutting the top side of my arm with it... i didn't break the skin except a small 1cm spot that didn't even draw blood, they were just scratches. I've had cat scratches worse than that... I started talking to my friends about it... two if them were supportive but I got into a miny argument with my ex, that's sorted now. But my friend told me to tell my boyfriend... so I did... and I got into a huge fight with him... I ignored him for the rest of the day but then I felt like i was about to cut again so I told mu friends again... they were no help so I decided to try and risk it again by telling my boyfriend... this time he was supportive... he ended up convincing his dad to drop him off and he rushed over as fast as he could and gave me hugs. He calmed me down so much that I fell asleep against him. Also today he gave me more hugs... but I feel like cutting again... like I'm not really sad or anything, I'm quite calm and relatively happy... i just feel like doing it again.. why?
I started cutting... what should I do?
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