Whats the best home remedy for coughing?

I was afraid last night, because my mom run to me with tears in her eyes and hold her heart. The reason? She cant breath good. It started when she cough hard, the way my mom cough, u can really hear its hard. When she cough, she vomits and then this vomit stuck up her throat and went up to her nose and stuck up there. But thank God we keep maging and she get back to normal. The only thing she is complaining now, is her heart in pain and everytime she cough, her back hurt and the pain will run from the upper left of her back and then went down. She said, she feel it is like an octopus spitting their poison, thats how she describe the pain. But its just the left portion that affects it. She is complaining her left under arm hurt too. We bring her to the doctor and said she dont have any heart problems, but she really have difficulty time with her nervous. She get panic easily. Can u guys tell me whats the best thing to do with this? Help please!