What should I do for an Injured Hamstring?

I have danced since the age of 3. However, when I started high school I quit for two years. Now I am back dancing after two years. I am only in my third month back but auditioned for the Nutcracker. I was never that flexible before I quit but now that I have started with a new teacher I am getting more and more flexible. I did the splits at my audition and got arabian. However, I am much more flexible on my left side than my right. When I did my right splits for the second time on my right side, I heard a tearing noise in my right hamstring. It was a little painful but I think the sound scared me more than anything. My audition was on saturday and it is now thursday. I haven't been going to cl and I am still in quite a bit of pain. It hurts down into the back of my knee and sometimes hurts when I straighten my leg. How long will it take for this to heal? and what can I do to help it heal faster considering I just got a part where I have to do the splits alot and rehearsals will be starting soon.