exercise? help!

I found out I was pregnant a few days ago. I thought it would be ok to continue with my workout regime which is a fit body boot camp (30 minute circuit with a mix of weights, resistance, cardio that is different everyday.). Felt weird about it today so decided to call and ask my doctor since I haven't seen him yet (they won't take me until 8 weeks and I'm only 4). They said absolutely not! No core workout, no lifting more than 15lbs, heart rate has to stay no higher than 120-140. Now I'm worried and paranoid I've done something wrong. Any feedback or reassurance please?? How do I know the little poppy seed is still ok? Am I being paranoid?