Could I have this disorder?

I would suggest maybe reading pages from people who have borderline personailty disorder describing how it affects them and if it hits a chord with you. I feel the only way you can truly tell is by seeing a doctor since most mental disorders cross over a little bit and its hard to distinguish one from another sometimes, they just get too similar...but self-harming is a characteristic of bpd...some just self-harm (called self-injury, self-harm, self. Inflicted. violence), but some do it within the realms of bpd...