Advice please

I had miscarrage in November at 7half weeks and period have come back to normal,and trying again,has this happened to anyone else of so how long did it take for you all pregnant as did test today and came back negative or it to early test as first response and says use 6 days before period and due on Saturday but had this before with early test and had negitive results then day before period it positive also I took test this evening about 6pm