Hello
Muscle tears mostly do not take more than a week to heal. It may be painful because it didn't get proper time to heal, apparently you didn't rest properly after injury.
I would suggest you to take hot fermentation and apply volini or any other ointment following some stretching exercises for hamstrings.
Next Steps
Give some rest to your legs and do not strain for a while.
Health Tips
Lie down with legs raised with the help of 3 pillows for an hour and do ankle toe pumps. This will help in proper blood circulation.