Can one breast be more sore and swollen than the other 8 days post op after BA?

One side always hurts more than the other so I wouldn’t worry too much about that however if you think you did something wrong and may have injured yourself then I’d suggest booking an appointment with your surgeon to be examined. 

In view of the fact you were reviewed at 1 week with no obvious concerns, it would be very unlucky to then have a problem subsequent to this. However, I am sure there is 24 hour cover at the hospital so it might be wise just to pop along for your reassurance and check all is OKGood luck!