pulled muscle in buttocks/hips??

Hello…I’ve been doing bikram for about 5 weeks now and am averaging about 3 times a week. I am pretty flexible and normal weight, but not incredibly strong in my legs and lower back. After practicing for about 2 weeks and loving it, I played tennis one day and the day after I felt a strain in my right hip….deep inside my buttocks and running down the back of my thigh. This pain has continued and is interrupting my practice, as my right side is totally tight and it makes it hard to do some of the standing poses. I told one of my teachers about this and she said it just takes time to heal.
My question is how long should I give it and is it safe to keep practicing? Should I avoid doing the poses that bother me…or just do them as much as I can? I don’t want to make it worse. I have been stretching before and between classes as much as possible.
Thanks for any advice!