Help!

So Ive Taken One pregnancy test ((week ago)) && It showed negative.

Than I went too a doctor ((Friday)) for another test came back negative, but the doctor said It could be too early to tell if I really am.

I was suppose to start my period last Monday and didn't ((like GLOW said I would.)) So I thought Thursday I would Start an still didn't.

But my breast have been supper sore an. Sensitive this past weekend..

Has this happened to anyone????