Is it normal to get period while breastfeeding?? Does it mean my milk supply will dry up?

Im 7 weeks post partum and had been eating like a pig so i can have a good milk supply...a few days ago i decreased my calorie intake a little bit (eating healthier) so i can lose a little bit of weight...today i saw a little bit of blood (sorry if its tmi) and im a little freaked out...i know you should not get your period while breastfeeding...does this mean my milk will dry up?