Is The Fetus Still Viable Despite Gestational Sac Findings?

Gd evng sir. My lmp was december 30th and nw am 49th day amenorrhoea. I checked my upt at 42days was strongly positive. On 43day I visited my ob.she said to do a bhcg becos she cudnt find gestational sac. Bhcg was 2654ng. Very next day again she vufnt find sac.so I underwent laparoscopy to avoid complication. But bilateral tubes were patent. Now am waiting for 1 week to do again go go for tvs.can I be still have viable fetus. I have breast fullness, tenderness pain frequency of micturation white discharge slightly no vomiting. Pls suggest me doctor. Sm 30 yrs and my 1st pregnancy.