I emailed a friend about that and she gave me some good tips so I will C&P them here...
It's totally ok to pump when you're engorged. Your breasts are not full of milk, it's lymph fluid that is causing the discomfort. If you empty them of the small amount of milk you're making right now, you'll just relieve the pressure, not signal your body to make gallons of milk. Don't worry about supply issues at this early date. Pump until you're comfortable. Actually, *not* pumping can sometimes - very rarely really - cause tissue damage if the engorgement is such that blood flow is restricted and cells start to die.
The last I'd heard was that cold packs alternating with heat were the best advice for treating engorgement. It's treated much the same way you would treat a sprain or muscle injury. Cold for the first day or so to slow down the swelling, then heat to promote circulation and remove and extra fluid, using cold in there too when it feels good. In studies done by lactation consultants, cabbage leaves have been shown to work the same way as cold compresses. They have the advantage of not being wet and of fitting inside a bra nicely, but they don't have any magical properties other than that.
If you feel feverish or have flu-like symptoms or notice a painful red spot on your breast, possibly accompanied by radiating red, spider leg marks, you may be beginning a bout of mastitis. The advice is still the same: nurse, nurse, nurse! If you don't feel better in 24 hours from the onset of these symptoms or if you feel really crappy all of a sudden, you may need to get antibiotics. Mastitis is not something to take lightly. It's a misnomer to call it a "breast" infection, because true mastitis is a systemic infection that affects the whole body. You will need a strong antibiotic like cloxacillin and you will have to take it for a minimum of 10 days.
Also here is a link which might provide some additional help: http://www.kellymom.com/bf/concerns/...gorgement.html
HTH. My breasts are engorged too but not nearly as bad as last night.