Hello. I really need your opinion about something. I am 28 years old and a have a very stable cycle every 29-30 days. This month i had unprotected sex with my husband during my ovulation time (days 13-14). On 9 DPO (one week before my next period) i had some brown spotting which turned out the next day (10 DPO) to look like an extremely light period with bright red blood. Usually i have many cramps in my period, but this time a had only some mild cramps for a couple of hours. This lasted 2-3 days and has nothing to do with my usual AF. Furthermore, my basal temperature had a dip on 10-11 DPO and then a shift again. I have never faced that before and i am a little bit worried. Is this a period? Or is it implantation bleeding? Thank you very much in advance.