It appears to me that changing pages on the Category Search changes the search query.
Steps to reproduce:
1. Category Search
2. Select +Ma/Fa, +Pregnancy, and update Voted to Not Voted For
3. Search
On page 1, it shows that I have 2182 stories that meet these criteria, and the search is `Showing: Ma/Fa [AND] Pregnancy`. But as soon as I go to page 2, it becomes 2282 stories, the search is `Showing: Ma/Fa, Pregnancy`, and it clearly appears that stories that I've voted for are showing up in the list.
If I then return to page 1 (by clicking, not by the browser back button), then it still shows the 2282 number.
I don't think the categories themselves matter quite so much here (I get similar behaviors with similar searches); it's more specifically that the "Not voted for" part of the query is getting lost on page turn.