burst like a kipper

Post coital state of a lady having engaged in a vigourous encounter with a gentleman of some proportion

Agnes: Awrite Senga, how did ye get oan wi' Boabie last night?

Senga: Aye, fine... Bit aff mer than ah could chew like. Ah'm burst like a kipper so ah am!

Agnes: Ya durty bint. Well played.