6 weeks today!

Hi everyone I am 6 weeks today and just found out 2 days ago. my first appointment with my ob is December 28th. I was wondering if anyone could tell me if I am putting my babies health at risk with my job or if i am able to keep doing what I have done for years?... I am a herdsman at a dairy farm so it is very physically demanding. I do anything from driving skid loaders to moving cows, pulling calves, giving shots, etc. At what stage in pregnancy should I be taking it easier on my body to not put my little one at risk?