help!!

Rebecca
Question for you guys! Per my app my ovulation period was at the beginning of the month I'm 11 dpo and I keep getting a bfn. The past two days I have had cramps and really sore boobs, and this morning I have none of those symptoms ..no bleeding af is due Saturday! Any idea on what's going on... should I wait to take another test.. is this a early sign of af... has anyone else had the same issues! Thanks a lot everyone :)