BPs are famous for not eating, particularly WC individuals. They seem to be able to go for months with no ill effect. Unless the snake is emaciated it should be fine for now. Check to be sure it has good weight - a healthy BP is a plump BP. Keep it warm and give it a hide box. Make sure it has water to drink.
This time of year I've had BPs go off-feed often. This is esp. true of WC snakes that come in from Africa - many femals are gravid and will not eat at all.
If your snake is WC, here's one way to get it eating. Get a breeder pair of gerbils, and plan on keeping them! When you get your first litter of gerbils, offer live hoppers to the snake. Once you get it eating hoppers, graduate it to larger gerbils. I found that gerbils can breed fast enought to out grow the snakes' appetite. Gerbils are natural prey for BPs, and BPs thrive on them. At some point you may want to switch to less expensive mice or rats - thats up to you - but get it eating first.
Also, you might take it to a herp vet and have it checked out for any health problems. Things like mouth rot, URIs, and parasites can all thow a BP off-feed.
Good Luck and Don't Panic!
John
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I am so not lesdysxic!
0.1 Creamsicle Cornsake "Yolanda"
1.0 Bairds Ratsnake "Steely Dan"
0.1 Desert Kingsnake "FATTY"
0.1 Black Rat (WV Rescue) "Roberta"