Since you may be facing a custody battle in the future, my best advice is to document everything and if he ever puts his hands on you again to call 911 (not only because no one should ever touch you but so there is a police report). I would also recommend not allowing him to be alone with your son ever until he can prove to you he is clean for an extended period of time. I am a big advocate of a hair follicle test. Drugs stay in your hair at least 90 days. As we all know urine tests are so easy to cheat and drugs don't stay in your blood for very long at all. I wouldn't recommend a home drug test as these aren't admissible in court and you may need it one day. I am so sorry you are going through this. You and your son deserve better.