I tore my left hamstring a few years ago, heard and felt a pop. Literally felt like someone hit me in the back of the leg as hard as they possibly could with a baseball bat. I could not bend my leg for several day. It happened on a Sunday, by Wednesday morning my entire leg was black, from glute to calf.
Keep it elevated, take ibuprofen (I like naproxen), use ice as needed, and don’t be afraid to put some warm creams on it when needed. You want the blood to circulate to help to heal it. I fell in love with a liquid muscle ointment called ThermaFlex that I got at a local feed supply store. Go to Google and search it, really good stuff, especially for muscles like that.
Do not stretch. Keep it comfortable and relax. If it changes color, it is torn. I do believe that a doctor will only operate if it is has been torn for less than 10 days though, could be wrong. I’ve heard that about pec injuries.
Start slowly. I started trying to walk up stairs, up the three steps into my house.
Ten days out from injury I was doing high box squats, leg lightly wrapped (top to bottom), and got stuck on the box with my body weight. 8 weeks later (against Dr. advice) I competed at one of the heavies shows in the country. Do what you can, when you can, and ONLY when you can.