refusing one boob

My LO has been refusing the boob that has the strongest let down. She'll latch on but when my let down comes she'll cry so I hand express a bit and try to put her back on but she'll refuse.. she's been doing this all day. I've tried laid back nursing and the hand expression... is there anything else I can do? Will she ever get used to my letdown? It makes it hard to nurse in public with leaking nipples and her pulling off all the time letting milk go everywhere.