Hello Madam, Welcome to Health Care Magic. I read your query and I understand your concern. Usually a greyish yellow discharge that is thick and has a foul smell, either after or before the period, is not normal and it indicates that you probably have an infection. In most cases, the infection is either fugal or bacterial. The cause of the delayed period might be the infection you are having. The most common cause of this type of discharge may be infection from trichomoniasis, which is commonly spread through sexual intercours. With such a presentation on my clinic, in order to give e definite diagnosis and rule out other possible culprits, including gonorrhea and bacterial vaginosis, I would recommend you perform a urine tests and vaginal culture of the sampling of the discharge. Trichomoniasis, gonorrhea, and bacterial vaginosis are curable with appropriate antibiotic therapy. Due to the cause may be a sexually transmited disease, sexual partner should be informed so that he may also get adequate diagnosis and medical treatment. Since the treatment requires prescription medicines, I would suggest you to meet the local Doctor to confirm the diagnosis. Hope I helped with my answer. Fr further concerns or follow up questions, feel free to ask again. Kind Regards, Dr. Ina