My thoughts:
1) If this is the first time you've had this injury, you should go to the doctor or a professional atheltic trainer. It MAY be a routine hamstring strain, but it could also be something else. Some injuries get worse with time, not better.
2) If you're pretty certain it is a hamstring strain, here is a link that might help you with recovery:
http://orthopedics.about.com/cs/spra.../hamstring.htm
3) If it is a hamstring injury, it is going to take quite a few months for it to completely heal. It is not uncommon for people to still notice tightness in a strained muscle even after a year. You will have to ease your way back into exercising it, and don't be surprised if you aggravate it a few times on your road to recovery.
4) The hardest part about recovering from an injury is figuring out if you are doing too much or too little. A good medical professional can really help you with this process.
Good luck! I hope it heals quickly for you.

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