Weight gain!!

Hello ladies. So I am currently 28+3 this is my first pregnancy. So far I have gained 40lbs!!!!! I don't eat unhealthy :( however I don't ever get to exercise. I work 10 hours a day, and by the time I get home I am exhausted. I know everyone gains differently, I'm just afraid I'm gaining too much. I still have 11+ weeks to go!  Of course having a healthy baby is my number one priority but, any advice at all to help slow the weight gain would be greatly appreciated!!