Torn calf mussle

Patient: Hello yesterday i heard a ripping noise and felt a servere pain in my calf . Went to the doctors who said they think i have torn a mussle. I have had no but have abit of swelling on the left side of the knee. And it us painfull and tight when i walk on it. Just wanted a bit more advise about how long to rest it and how long i need off work