Im 39 weeks and 3 days pregnant a day after my ob checked me and today i have brown discharge with menstrual like cramps could i be in labor already?

Cramps: you may be having Braxton hicks contractions, and your mucus plug may have come out if you are having contractions every 5 minutes and you feel a gush of fluid then you are in labor. At this point you are in the early stages.

Maybe but unlikely: If your "Ob check" included a digital internal exam of your cervix, it is not unusual that you would experience cramps and discharge. These may be signs of early labor but may subside spontaneously ("false labor"). Until you have persistent regular uterine contractions associated with gradual changes in your cervix, which are the way normal labor is diagnosed, you are probably not in labor yet