DUE DATE! And questions?!

Savana • Married to my wonderful husband❤ my babygirl is due in March 👶🏽
I got a guess date! Which is very exciting, March 22, 2017. At 5 weeks now. Been exercising is this good or bad for the baby? When should I stop lifting stuff as if My job is very hands on. And just any tips to help considering this is my very first pregnancy? Thankful for your comments 😊 also my line got darker since Friday!!