My two sims are on level 8 woohoo score yet they both come away with a ''bad experience, from bad woohoo''!!?? this has only just started happening..could this be a bug?

I don't know but here is maybe a good description of what it is all about and how you can get rid of the moodlet and what you maybe have to adjust in their skills levels.
post28127#p28127

fEDuPwITHrULES,

​​​​​​The link C-Dark suggested is helpful but I want you be cool with that. It's not a game bug.
My Sims have a high level of Kama Sintra and sometimes, when they whoohoo with each other, they get this moodlet.
Don't know why it happens, but I suppose maybe they were not in the mood to whoohoo... hahahahah just joking.
I delete the moodlet eventhough they have no impact in their humors. Delete it by Master Controller.