hi dear , i understood your concern, my best advise is better you and your husband should meet a gynecologist. your problem will be easily solved. but anyway answer for your question. you should subtract 14 days from expected date of menstruation. example you got menstruation on 14-19/10/2016 expected date of your next menstruation is +22 for 1st day of menstruation=====5/11/2016 now subtract 14 days====22/10/2016 will be expected date of ovulation. but though please concern doctor. due short cycle which may be due to hormonal imbalance which may preventing you from getting pregnant. thank you