I have a very tight chest with a green mucus phlegm I’m coughing up. A red sore throat, making it difficult to swallow. What is this and can any over the counter meds work for it??

Infection. It appears as if you have an infection. You need to see an internist or family practice doctor.
You probably have. developed a serious infection. Although OTC medications might help you since you are young it would be prudent to be evaluated by a health care professional and receive targeted therapy so you will recover more rapidly.