I can't comment on hamstring specifically, but over the winter I had a strained calf, bad achilles tendonitis and posterior shin splints, as well as anterior shin splints for a while.
It took months to go away, and even now the ankle joint is still stiff, but I basically didn't run until it was better. I took 2 weeks off at first after a physio appointment and some sports massage, but then had pain when I came back, so after 3 days back running i had to stop. It got to the point that it hurt just to walk, and I was so frustrated with not being able to run, that I stopped. I did cycle machine, cross trainer, swimming and rowing intensively for a month or 6 weeks after that, so in total like 2 months off running completely, and then when I cam back I did like 1 minute jog, 1 minute walk for 20 minutes, then 2 minutes, 3 minutes etc. for about 2 weeks, before moving up to like 10 minutes, 20 etc.
I had in total about 3 hours of PT/sports massage, including acupuncture (even when I started running), and it as all very helpful. Taping is also amazing, I don't know if it would work as well for hamstring, but KT tape for my achilles/shins, just kept on for 5 days at a time, running or not, was a lifesaver.
I was also icing, using foam roller/stick, anti-inflammatory gel at the beginning. Physio thought it was probably some hip/glute imbalance, so I was doing low rep/high weight 1 legged gym work, and that was very helpful. However, I got lucky that I didn't tear the muscle/achilles, and it sounds like you could have a tear, which is going to be a problem for much longer, if not forever, I think. I would stop doing things like deadlifts, get acupuncture and regular sports massage, as well as rolling or using the stick 3 or 4 times a day, with ice, and just lay off the running completely for a month at least and see how it goes.
Good luck!