Hi Umbrella and (((Hugs)))). I'm so sorry for your pain today but I'm really glad you posted and got this stuff out on the table. It will help.
If you don't have the money for a counselor, there are many drug abuse hotlines you can call 24/7. Counselors are available to talk to you anytime about the nature of addiction and discuss your options. (example: 1-800-COCAINE)
I also strongly encourage you to keep a number handy for your closest domestic abuse counseling center and consider making an appointment for counseling, which is usually free. The national hotline number is 1.800.799.SAFE (7233)
His use of cocaine is very likely the cause of his irritability, anxiety and restlessness. As he continues to use he will require more and more of the drug to achieve the same level of 'pleasure' that he got initially and his risk of serious physical damage (stroke & heart attack) will increase dramatically -- this is especially true if cocaine is mixed with alcohol. It can also cause severe paranoia and auditory hallucinations.
Talking to his mother will most likely not have any real or lasting results, nor will your crying, begging or bargaining. Frankly, he sounds as if he's in a full-blown addiction and, at this point, your best option is to get educated, attend Nar-Anon or Al-Anon meetings, or see a counselor so that you can evaluate whether this is a road you want to travel. It's a very tough one.
Above all, be safe and do not take any risks. If he is volatile and showing signs of rage or violence of any kind -- GET OUT OF THE HOUSE or CALL THE POLICE. Do not take chances with your safety.