Wow, that is crazy how they treated you. So sorry for that and all you've been through. Hugs!
After my first c-sec I got a very low grade fever on the day I was going to go home (would that be day four?). I felt completely fine and I don't think it even hit 100, but they took it very seriously and put me on IV antibiotics and kept me there for three more days until fever was gone for 24 hours, I think. It was crazy bc I felt like I was on top of the world.
Anyway, I have told a hundred mama friends about it, at least, and I don't remember anyone ever saying it happened to them, too. I think it's probably pretty rare. And I can't imagine it's something that is likely to happen to you again. I had a C w number two also and didn't have a problem w fever. Actually, w my second I was really sick -- pre-e bad enough that my kidneys shut down (or maybe that always happens w pre-e?) for a day or so -- but still felt on top of the world and was allowed to go home on time.
I am certain that I felt 100% fine by maybe 3 weeks or earlier both times. I was and still am numb around the incision, but no pain at all. I wonder if you should see a different doc about that.