Could i still have hope

OK AF was due July 9 here it is the 15 almost the 16 and still no AF. I have had cramping for about week an half and headaches that's all. Well last night I had some spotting but it was stop by this morning. I have made an appointment to have blood test done next week. I have took test after test and they been bfn. But what I was wanting to know has this happen to you and still been pregnant? I have not had a period in 38 days.