The wonderful and terrifying 2nd trimester

Hi ladies, i'm almost 15 weeks and am feeling so nervous the last few days. How do you know if your baby is ok when you're too early to feel it, and don't feel sick anymore. I know the 2nd trimester is easier for most i'm not sick, no cramps, still tired but not as bad as a few weeks ago, my belly is starting to round, and my boobs are huge but don't hurt as much. I'm trying to stay stress free but i've had a lot of losses and am dealing with high blood pressure and diabetes already. I just wish i could know for sure the baby is ok.