Many people don't have the same curl pattern all over their head. When I stopped using heat and started taking care of my hair the roots grew in more tightly curled than the rest of my hair. The back is also more tightly curled than the front. I just work with it and use products that are best suited for my hair.
Hair does take time to grow, not everyone's hair grows at the same rate and it could be that your growth rate is slower. The length you are able to achieve is also determined in part by your genetics and hair growth and shedding cycle.
Sometimes with curly hair it can be hard to see just how much growth you have achieved due to shrinkage and tighter coils.
Sometimes when I flat iron my hair after 6-8 months of going curly I can really see how much growth I had.

Don't give up. Keep taking care of your hair and try to find the right products.

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