I have a normal menstrual cycle every first week of the month. Then I was bothered that it was delayed now for two weeks. And my menstrual color is dark and sticky brown. Also instead of seven days period, I was bleeding for about 2 weeks until now. The first three days is sticky dark brown and the 4th to 10th day is dark red. And the following days until now back to sticky dark brown. I am so worried because it is not my normal period. Is this normal or should I consult to a doctor?