Missed Period- side effects of stopping Krimson-35?

Recently after stopping Krimson-35 (taken for P-Cos) after 5 months and having unprotected sex I missed my period. But I took the pregnancy test twice but they came negative. Then I consulted my doctor and she gave me Gestin 5 mg tablet to take twice daily for 5 days. But even after completing the course I had no period. But I have developed vaginal etching, pain during urination and pain in left hip and thigh till the foot. What do you think are the symptoms are? What are the possible side effects of stopping Krimson-35? When I will have my next period ? Is there any possibility that I am already pregnant? In case of ectopic pregnancy will the pregnancy test be negative or positive ?