I think i’m pregnant

Patient: Hello my name is Raquel and I think I’m pregnant.I have a nomal period cycle my period most time come in the end of the month.my lost period was on the 23 aug I was sexualiy active 27 and I remember the night feeling not my usual self I become sick it was feelingtire alot lighthearted, heatburn, dizziness i been having alot of cramps, backache,moody and i also did experience some Spotting it was very light.I never experience that befor, i find to be having alot of lower back pain.I also feel as if My uterus got bigger and I find it hard to sleep at night.My biggest quostions is why does both pragnancy test blood and the pie tests come back negivite? I have a strong feeling I’m but it show negivite I guss I going to have to wait untail 23 of sep to see if my period come. Help me please.