Weight Gain

I am only 10 weeks and have already gained a significant amount of weight.  I had already gained 10 pounds before getting pregnant after having an early miscarriage.    Every time I feel nauseous I eat a little and I keep gaining. I exercise for 30 minutes daily. I have made some unhealthy food choices lately but that's what my stomach wants. My dr says I can only gain 15 lbs. Would it be safe to lose a little weight?  I think it would make me feel better.