7 positive at home pregnancy test.. negative at the gyno

I went to the Gyno today to confirm my pregnancy after getting seven positive at home pregnancy test. The test at the doctors office came back negative… They drew blood and want me back on Thursday to make sure my levels go up. The Gyno told me that she has seen this happen before especially since I am testing positive pre-period. I even tested when I got home from work today and got a positive. I am trying to stay calm. 

So my question is, has anyone had this happen to them before?

Please do not just up-vote this if you have had this happen. My excitement went from so high to so low.