Confused if im prego or not ??

I am 10 days late on my period I already seen the doctor & blood test was negative but 4 home tests came out positive !!!!! i still feel pregnant I have all the signs and a lil cramping& still no bleeding i have regular periods and have been trying...ive heard it happens to alot of women sometimes your levels are too low for even blood test ?!????? #helpp #confused