It sounds like pleurisy actually, which would be related to your chest infection, not to baby. It's an excrutiatingly painful build up of fluid around the lungs from an infection. I had it when I had pneumonia and it is awful. It's more painful than giving birth! I had rib pain with my first breech baby (but not my second) and it was more a dull ache, not a sharp one. The fact it's worse when you cough and you are currently being treated for an infection makes me think it's likely pleurisy. You don't really need to do anything other than take the antibiotics and rest. Don't think about going into work. You want to get better. I got really sick with pneumonia (much more severe than it sounds like you have it now thankfully), but the pleurisy lasted on and off for 6 months. You don't want that. So rest now and feel better before you try to go back to work.
I should add though that it is normal for pleurisy to last well after an infection has cleared, so keep taking your antibiotics. It isn't a sign they aren't working as the fluid is related to inflammation, not to the infection itself (the infection is inside of your bronchial passages and lungs, not around the outside). But the fluid builds up because everything is so inflamed. The infection will go first and then the pleurisy will go. Mine lasted really acutely about a month or 6 weeks when I was really ill, even though the infection had cleared. But it kept coming back because my lungs had been so damaged (unlikely to happen to you though, I really was very ill, in hospital on oxygen, etc.). More than likely it will clear a week or so after the infection if you take care of yourself.
My pain was more right side rib during pregnancy. I am 19 weeks postpartum and I'm still suffering with rib pain(both sides), I have been back and forth to doctors. I am waiting on hospital appointment to get scanned as doctor thinks it could be gallstones.
My rib/back & stomach pain seems to be getting more frequent.
Good luck op, hopefully baby is just lying a certain way and moves for you 🙂
I had hideous rib pain with dd1, she had very long legs (still does!) and liked to push them straight out and under my ribs. It was incredibly painful and bruised my diaphragm and left visible bruising In the area. But she was head down and born in 3 hours! Apparently if you have bruised ribs its more likely your bump is tight and so stomach muscles stronger and makes labour faster (I’m dubious about this myself, but makes for some nice pseudo science!)