Suggest Remedy For Irregular Menstruation With Weight Gain

hi ive always had normal periods but starting in 2014 i started to mis my period for 2-3 months and now the last time i had my period was in october 2014 i have taken pregnancy tests and they are all negative last year i went to my dr and they did all kinds of blood tests and everything was normal. i feel that i have been gaining weight. whats the next step.