I have a very good friend who is going through this right now with heroin. The advice from twoguns is solid - that will really help to combat the withdrawl symptoms. HumanTarget is also right on - you will need something to help with the anxiety. I would go see your doctor. They can really help you with this. Keep your head up bro - you can beat this!
My doc who presecribes my pain meds, perscribes Suboxone for people suffering from withdraw from opiates!!! You doc should prescribe you those, but ask about side effects!
I read a report where one Doctor did the following: Xanax for the anxiety you are going through, Imodium AD for your sick stomach and it also helps ease the withdrawal for some reason, Tylenol Flu or any cough syrup that has Dextromethorphan in it to help with the major aches you are having. Best of luck bro. Be strong.