Firstly congratulations! :)
I travel a lot for work and for leisure, and didn't reduce my flying (mostly short-haul for me too) because I felt OK and didn't have any complications with my pregnancy.
What I did was take longer over my work trips, and minimised trips with very early or late flights by staying an extra night if necessary so I didn't get too tired. I also had prescribed and properly measured and fitted compression stockings that I always wore when flying. Plus, because I was doing lots of flying before pregnancy, and it sounds like it might be the case for you, I didn't find it too stressful because I was used to everything.
And another thing, carry some food with you all the time. Don't assume that the airline will provide you with food that you can / want to eat on the plane. What with the long flight delays, cancellations, in-flight diversions, in-flight meals consisting of parma ham and blue cheese, missing meals due to long meetings, I was glad to have some emergency food supplies in my bag.
Also, as mentioned above, check with each airline you are likely to fly with to see what their rules are about needing a medical fit to fly certificate (typically I found after after 28 weeks, but carried one before just in case), and how far into the pregnancy they will let you fly. I have found it varies greatly with different airlines. And do consult with your Dr or midwife, and be guided by how you feel.
Here ends the lecture! 
In the end I flew up until my 34th week, doing 60 flights over 18 trips! 