Going back to work after maternity leave

My little one is going to be 9 weeks old on Saturday which means I have only 3 weeks of maternity leave left. I have absolutely loved every minute of being home with him and watching him grow and change each day. I'm starting to feel anxious and horrible about having to go back to work and missing out on precious time with my son. If you have returned to work already, how are you dealing with it? I could use some advice!