It sounds like you may have a buildup problem and an imbalance. Have you tried using a clarifying shampoo after taking the braids/weave out? You will need to get that scalp back in balance and the first step is to make sure it is cleansed. I would even suggest a scalp exfoliant at this point.

When the braids are in, you need to wash your scalp at least once a week then use a light oil when your hair/scalp is still damp.

It is going to be a little bit of trial and error until you find what works for you. Don't give up!