when to moderate workouts?

My mom and sister have me a little freaked out about working out now that I am pregnant! I stopped working out during my last pregnancy more because of exhaustion and just stuck to walking for most part. It took me almost 2 years PP to get the workout itch again when we were planning our wedding to finally lose the baby weight. I work out at home doing a mix of some 21 day fix and p90x videos along with yoga and some self created workouts using weights and doing cardio. I am not exhausted like my last pregnancy, but definitely nauseous now. My sister said I'm not supposed to work out during first trimester at all. But I find the days I don't work out the morning sickness is so bad all day long! I work out for the mental feeling more than anything but worried I'm putting myself at risk. I want to stay fit for this pregnancy but so hard to get a real answer on what I can and can't do! What have your doctors told you fit mommies? I go on Wednesday for first appointment so I'm obviously going to ask my OB but just looking for some feedback!