Does my daughter have a learning disability?

I am an American living in France. I have a daughter who will be five in October. Her father and I have been trying to teach her to count since she was 3. But she cannot get past No. 5. She can remember up to 10 temporarily and only if she counts quickly and if we have just reminded her how to do it. If she counts slowly she can't get past 5. I have tried to get her interested in counting with several different games (hungry hippos, flash cards, exercise books, etc...) but nothing works. She is starting kindergarden in September and I am afraid the other children will make fun of her (which they will, if this continues). I am also afraid that her teacher will label her as being "slow". Any suggestions? Any ideas on what the problem might be? Any Solutions? Thank you very much.