I was also pumping, had an infection as well, and decided to drop the pumps, but I didn't stop it completely, just fewer pumps for a few days till my boobies healed. Yes, the milk decreases, but it increases again once you start pumping more and more. This was my experience, but I would definitely see a doctor. Hope you feel better soon!
Ouch! Contact the breastfeeding and lactation support uk group on Facebook they have experts giving advice who will reply within a day. Can your gp also give you some safe Painkillers? I have codydramol for endometriosis which is safe for BF and cleared by many doctors Also why not consider taking stronger Painkillers if just for a few days, you could pump and dump the milk from that time or indeed for until you're healed. Give cow milk in the meantime if tolerated. No reason to suffer to keep the supply! Please also get a new pump or at least new breast shield for when it's healed as that may be causing you to get reinfected with the fungus
Personally, I would put my health first. If your body needs to heal then, let it! If you continue to pump, you could make the condition worse which could result in having to stop altogether. Look up relactating, as it is possible if your supply gets low due to the break.