Hello I Had And U/S On 25th Of January And

Hello
I had and U/S on 25th of January and i was 8 week pregnant at that time according to my last period date but my baby was measured only 6 week on that day, then dr told me for a follow up U/S after 10 days so i booked my appointment for 9 of Feb. but yesterday on 4th of Feb i had brown color discharge just lil bit one spot only. So am just concern whether it is a bad sign.
Thanks