Hi, and thanks for your medical question on eHealth forum
If you have not had your periods since March, you should consult a gynecologist. Since you are not having periods, there are bound to be problems that hamper conception.
Since you have pain in the lower abdomen area you should rule out pregnancy. If there are no periods, it is difficult to know whether you are pregnant or not. Hence take a pregnancy test.
If you are not pregnant then it could be due to cystitis, polycystic ovary or due to inflammation of bowel.
Since a confirmed diagnosis cannot be given on net please discuss these possibilities with your doctor once. It would be a good idea to consult an infertility specialist. Hope this helps. Take care!