Confused

On Jan 7 /2019 I had my tubal reversal procedure the day after the procedure I started what I think is my period a was heavy flow for 7 days so I did my calculations and had intercurse with my fionce jan 28/ 2019 I’m pretty regular with my periods prior to my procedure some months I would get my period after two weeks and it has always been heavy flow now after the procedure I’m 4 days late and I have tested and they all have been negative but no period I am so confused and puzzled I’m not sure what I can do.