I just found out i am prego #2 my first is 5months?

hello. i found out today i am pregnant with my second child. i have one already she is 5 months now. i want my children to be close in age. however i have been trying to lose alot of the fat since the birth of my daughter. i exercise and still have not managed to lose a mere 3 pounds. how can i lose fat that collected on my back whn pregnant and also minimize my before they get bigger again? which exercises can i do that will help me to burn the fat and feel healthier before #2 gets here?