Haven’t personally been through this but some things I’ve heard of to help are: Relieve a little big by hand expressing but do not empty the breast otherwise it will tell your body to produce more. Cold Cabbage leaves in the bra help provide relief and also reduce the amount produced. It will take time for your body to realise it doesn’t need to produce anymore.
Sudafed can reduce your supply, and I would pump or hand express just enough to relieve the pressure x
No experience on this but trying to help. If you are able to buy a breast pump that is wearable it may help. That way you can still give your baby breast milk if that is what you want. I have a combo fed baby when I cannot breast feed I pump to relieve pain even though most times I pump and dump (solely for the fact I am forgetful when I was storing it) and that helped me a lot