17dpo No AF and BFN!!

Really don't know whats happening with me this month! having mild stabbing cramps last few days and sore boobs weeing more so pregnancy symptoms are there, I've always had a 28 day cycle or lower and the only time previously I've been late was when I did fall pregnant but as we weren't TTC then didn't actually test until I was 9 days late and even then the line wasn't dark ended in MMC, am I still in the running?? Should I request a blood test from the doctor's? used FMU today and got BFN no sign of AF either used a 25 Miu pregnancy test.