Is this normal? what's going on?

My period was due on Wednesday or Thursday. I took a test test on Sunday and it was negative. I took another test on Thursday, and it was negative again! Bought a different brand of test, took it this morning, and it was negative! Could I be pregnant and it's just not showing up on the test yet? I think i'll wait a week and see if maybe then it will show up... Really want that bfp!