You have several problems here ones that are leading to self destructive behaviors. Your use of pot was most likely self medicating, not really 'drug abuse'. you were self medicating to 'deal with' issues. Now that you have decided to stop medicating, those issues that you have been treating have come to the forefront. You are trying new ways to 'treat' the symptoms of an underlying deeper ailment. Cutting is a form of 'self medicating' - attempting to relieve the symptoms.
Your best bet for pot and other drug addictions (even if you are self medicating) is to enter into rehab. Most likely you can go to a rehab in your locality and tell them your situation financial and otherwise and they can get you on the road toward getting the right medical assistance you need.
Since I have no idea where you live, I will have to give general directions on how to get help.
Most US cities have a public health center that deals primarily with giving free health and keeping track of the spread of infectious diseases. However most will have at least pamphlets telling you how to get free health care in your town/city/county. They will know all of the state, county and city level programs for health care in your area. There may even be programs specifically designed to deal with 'cutting' in your area.
Most areas have 'free' clinics and 'tax payer paid' health care programs for adults. However since you have a job then you may be looking at sliding scale bills.
If things are too overwhelming you can admit yourself via the Emergency Room for emergency psychiatric assistance. Mind if you say you want to hurt yourself and or want to commit suicide they will put you in a 72 hour hold, holding you for observation in the locked mental health ward. Cutting is a gray area when it comes to 'harming oneself'. If you admit to wanting to killing yourself, they are legally obligated to admit and hold you.
If you have a General hospital or a county hospital it most likely has the offices for 'free' health care there, or at least a waiver for current medical bills that you are accruing. Go through the main entrance and ask in the lobby where do you go for billing questions, there you can ask them what sort of programs exist on the city and county level to assist you.
Without knowing much about you I think you suffer from a form of depression that is being made worse by stresses and problems with the job. If this depression just started the past month or so, or if every winter you get 'down' then you most likely have Seasonal Affective Disorder.
Seasonal affective disorder (SAD) - MayoClinic.com
SAD is still misdiagnosed, and mistreatment compounds the problem. If you are treated for general depression (drug therapies) when you actually have SAD then chances are you will go from merely depressed to suicidal. YOU need to sit down and think about your life, how long you have been depressed and mention to any health professional if your depression hits seasonally or not.
You most likely need both a psychiatrist (MD) and a psychologist. The psychiatrist will prescribe medications to help you deal with the emotional stuff, the psychologist will use therapy, and give you tools to cope and manage whatever feelings you have.
You have not stopped your 'addiction' (Self medicating). While you have stopped smoking pot and stopped stealing, you have just switched addictions, switching to cutting for pain relief. this is not the same thing as 'true addiction', this is self treatment of the symptoms of a deeper problem. Most folk who self medicate with alcohol, drugs, cutting, etc find that the 'addiction' pretty much leaves them once they start treating the deeper issue.
If you refuse to seek professional help, then get a bag of pot and start smoking again. Pot is marginally better for you than stealing and cutting yourself as a way to self medicate.
However I would prefer if you seek medical help and start dealing with the underlying issues.