I know this is taboo, but I wanted to share with you that both my kids prefer sleeping on their stomachs.
Shortly after we brought our children home from the hospital, they both preferred to sleep on their stomachs. My son, who is now 3 years old, would sleep through the night on his belly. My pediatrician was appalled and made me keep him on his back. But he didn't like it, he would cry. Luckily, we were in a small condo at the time and our bedroom was very close to his nursery. I would let him sleep on his belly but I would watch him often and constantly check on him. About 19 month ago, I had my daughter and shortly after I brought her home from the hospital same thing. she prefers to sleep on her belly. Now that it was the second time around, I wasn't sweating it as much. I don't put anything else in the crib, no blanket, no pillows. Just the child in a fleece one-piece pajama (with a thin pajama underneath) in the crib.
I went back to work full time after my first child and only had 12 weeks maternity leave. I totally understand, it is so stressful. My son cried every day that I dropped him off at the daycare, then I would cry driving myself to work. argh. I do NOT miss those days. I am home with both of them now. Phew.
Good luck to you on your adjustment, back to work, it will be fine. Best wishes!