Sorry, wrong of me to assume you were male. Same can still apply to you though clitoral engorgment takes a fair bit of blood, rest goes to labia, vulva etc. Basically, when you're horny, you're body diverts majority of blood flow away from organs not immeadiately needed (i.e. the stomach and guts and after, rebalances the flow to continue digestion etc. It can cause a sick feeling, which you may link to feeling disgusted with time. Certainly not uncommon, and AFAIK, not a hormonal thing.