Has this happened to anyone else?

Need some hope please ladies.. 

First day of last AF was 18th October 2017. 

I did a clear blue digital hot on 16th December 2017, said a bfp, it stated stated Pregnant 3+.. 

Went doctors on the 18th December because I had some uncomfortable aches and then, the pregnancy test there came back negative.. And I continued to get negative tests for 4 more days at the doctors and hpts.. 

The doctor said I should come to terms I am obviously no longer pregnant... But I had no bleeding so I dont get it? How? 

Anyway, I've still had no AF since October, it's now 31st December 2017 and I look pregnant, I feel pregnant, I have symptoms of pregnancy... And have just done another 2 hpts due to still feeling pregnant despite the doctors telling me I wasn't... 

And both are bfp's.... 

Has this happened to anyone else before? Am I pregnant then? And if so why after a pregnant 3+ did I get negatives for a whole week?? 

Anyway, happy new year! Any advice I would really appreciate.. Or anything like this happened to anyone else??