No, self-injury and suicide are different. Each individual has their own motivation and mix of self-injuring and suicidal feelings. But, self-injury often represent the prevention of a suicidal period. In fact, self-injury can avert suicide and may be a survival strategy. It is frequently the least possible amount of damage a person can do and represents extreme self-restraint.
If you self-harm, there are resources available to you...Please feel free to check out these websites, and add to this post. Together, we make strong medicine.
http://www.nshn.co.uk/resources.html
http://www.selfharmalliance.org/
http://www.sisupport.org/
http://www.psyke.org/
http://www.siari.co.uk/