Help/ advice- cramping since ovulation

TTC for 4 months now and am trying saliva ferning to track Ovualation as OPKs weren’t coming up with a positive. This month I managed to see when I was happened and so we DTD. I’m currently 10-11 days past DPO and have experienced cramping and pelvic pain on and off over the past 2 weeks. Plus bloating and constipation. AF due 16th Jan. are these signs of AF coming or could it be a BPF. I did a test at 7-8DPO and it was negative.

Any help, advice or experience would be extremely useful and reassuring. 😊