Hi Jasminnie, cocaine is very very addictive and unfortunately your son is at his stage of addiction denial. Your only option is to command that he gets help, professional help even if he think he has a problem or not. Don’t take the “I’m not using” because you sound far too clever for any of that, your self testing him! He’s an an addict in denial so Challenging him to complete a test in front of you then setting up a meeting at an addiction ctr would be his only option, and thats what you must present to him. Trust me! All his money and any money that you have givenloaned him has been spent on this Dirty drug. I feel for you but I feel for him because it’s an unforgiving drug. Good luck