engourgement at night

Ev
Help! My 5 week old has been nursing all day and for the past week she's slept a 5 hour stretch each night. Instead of enjoying those precious hours I'm up trying to manage my crazy oversupply! The first few nights I could just hand express some off and hold out until she woke up but after 2 days of cluster feeding every hour during the day my breasts are so engourged I've had painful plugged ducts and had to pump. I don't need the milk and I'd much rather be sleeping at this point. Any tips on how to balance things and cut out the pumping? I'm worried about mastitis. I'm also considering trying a dreamfeed since after this 5 hour stretch it takes an hour to get her back to sleep and then she wakes up again two hours later. She usually goes to sleep around 10pm, then wakes at 3 to 3:30. Any thoughts or advice?