Bowel Movement Issues, Have Dandruff, Pimples On Face, Shoulder, Head, Back. Why?

hello doctor... i have problem with bowel movements...most of the times i have bowel movements everyday but sometimes once in 2-3 days. For every bowel movement, i should eat breakfast and then only i have bowel movement (i think then only i get the pressure for bowel movements) . And when i pass stool , i feel still there is more in there and not feel total empty which i ideally should feel. I am a 28 years old girl. I have started my periods at the age of 15 years. till the 15years, my skin was very nice, without any pimple. Even my hair was very thick and no dandruff , no white hair, no etching in hair, no pimples on face, shoulder , back and head. But since i have started my periods, i am having all these problems. i have tried 3-4 allopathic and homeopathic treatments but till the date i do not get the permanent cure of it. All these treatments have 3-6 months effect. After this period from treatment, the situation same again. I think, having not regular and clear bowel movements is related to this. So can i have a solution for this which is permanent. Please suggest me something. Thank you in advance.