Ovulated but no period and BFN on 23dpo.

Hi , My lmp was on August 11, I was on fertility treatment with hmj injections and this is the first cycle. I have 2dominant follicles on left ovary.on 15th day of my cycle i.e August 25 doctor gave me HCG 10000 shot. On 17th day my ovulation is positive no DF on that day.I am in  dydrohope from the day of ovulation. On 9,10,11dpo's I had light cramps and light pinkish brown spotting that I never had before. On 18dpo doctor asked me to come after took upt it was negative and she again asked me to come after 5days after repeating the upt also she mentioned if period comes within 5days asked me to stop dydrohope. Now I am in 23dpo no period and no postive pregnancy. Yesterday night I had brown spotting  after that I haven't had anything attaching the pic, I am confused if it is period or not ? Should I stop dydrohope?And what could be the reason if the ovulation is positive and no period what's happening in my body?