Technically over weight and pregnant

Hi everyone! I'm about 6 weeks pregnant with baby #3. I'm 5'5 and I weigh 185 (imperial) this past year I've dropped 75 pounds and I'm still in the eat right, watch calories and work out mode. I know now isn't the time to lose weight. But I can't break this habit I've formed. I know I'm still "heavy" and I wanna watch my weight gain because with my first it was " well I'm pregnant, I can do what I want" and with my second I was a little more careful since I got so big with my first. I haven't seen the doctor yet, but do any of you ladies know if lifting weights and continuing with my workout is fine? I'm using common sense. Less weight more reps, I've increased my walking but with a tad of a slower pace. I've also been eating around 1200 to 1300 caloric intake a day with my prenatal. And burning maybe my guess is 400 calories through workout. I've also increased my water intake as well. Also meal planning has been big. I'm just unsure of how many calories I'm suppose to intake daily for my weight so its healthy for baby.