Ruptured eardrums can be caused by trauma and ear infections. Since you know that she has an ear infection, this is most likely the cause. The problem is that infections can be bacterial or fungal and there are different treatments for each. The ear drum does not usually need surgical repair. There is a small danger of infection that spreads but I would not be overly concerned. I would be more worried about vestibular disease which can produce stroke-like symptoms in your pet.
Let me know if you still have questions.