ICSI 7 days past transfer

Hi to all,
I am 29years old (will be 30 in two months), i went through the ICSI procedure 8 days on my day5 with one embroyo.
The transfer was initially intended for day 3,( with two embroys) however due to complications and after three failed attempts,the doctor and the embrologist recommended for day 5 transfer (with one embroyo). We went back on day 5 with all the hopes. The trasnfer was done successfully. But last night,day 7,past my transfer,i spotted some bleeding ,i was worried. And phoned my nurse and she asked me to wait. In the morning, i had enough bleeding to use a sanitary napkin. I have cramps and pain. My blood test is due in three days.I am in agony and dont know whats going to on. I called the clinic and after speaking to my nurse, she said i am getting my period and the ICSI cycle didnot work for me this time. I still have hopes and feel its gonna be ok. Is this bleeding normal? What makes it bleed? Can i still find myself pregnant after three days? Keeping my toes and fingers crossed. Please advise. Thanks a ton.
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