I'm so confused. Was I pregnant or not???!!!

Please can anyone advise me- I'm just so confused.. :( 
I have a regular as clockwork cycle- af is only ever maximum 1 day late/early, and that is rare. Also, I suffer from really severe pms and I am fully aware of my body and symptoms as I have been tracking for some time.
2 days before af I was violently sick, did a blood test but it came back negative. 4 days later still no af, 3 home tests came back positive. 
pregnancy symptoms began; sore and growing breasts, extreme fatigue, frequent urination and, importantly for me, a lack of those pesky pms symptoms. 
Ten days later I got serious cramps, and spotting. This worsened and I went to the doctor. I already knew that I had miscarried, but what the doctor said baffled me.
She said there was no sign of me having ever been pregnant, and my hcg level was only 2!!!! 
I find it hard to believe that I was never pregnant- what were the symptoms and 3 positive tests about? And where was my period?!  
Does anyone have any answers?