When to take a test ?

I personally feel off this period go around , my boob's have a new pain and my cramps are minor and come and go . We have a celebration tonight and I'd like to have a few drinks . Although my period is due tomorrow and I also am at work already and my tests at home . I know they say to test in the am , but when did you test ? What time of day ? And before period due date or after ? :) thank you ladies