7 days late, negative tests?? Mild cramping and prominent blue vein on breasts?

So heres the story, the day after my last period i started cramping everyday as if i was going to come on my period for a whole 3 and a half weeks , then it eased up for a couple of days and then came back again although this time i assumed these must be the symptoms of my period which was due the folling week. I had all the normal symptoms- cramping bad headaches but my period didnt come infact when the day came the cramps got less and less and im now 7 days late for my period, the cramps have mildly returned and my breasts feel enlarged and have a prominent blue vein as it looked in my previous pregnancys- but heres the thing, ive done 2 hpt and both were negative . After the first test i went to the doctors and she was sure im pregnant and just told me to wait a week to do the test but its negative so now i dont no wat to think. Any opinions? Has this happend to you and you were pregnant?