My future son in law is in terrible pain from an accident that happened on a construction site. He became so tired of taking pain medication that he just stopped taking them around 2 days ago. He has not been feeling well - nausea, vomiting, sleeplessness or can't sleep enough. I cannot convince him to seek medical attention. Are these symtoms normal? Should he go back on the medication (not the full amount he was taking) and then taper off? I am very concerned.