Sounds like blocked anal glands - Mika gets those sometimes and it's a really easy procedure for the vet to empty them out for you. We usually see relief right away!
Yep. Blocked gland.
Unfortunately, it got infected, and the vet couldn't express one. So now, $300 later, he's on 2 types of pills and wears the cone of shame.
Oh no, not the cone of shame! Poor guy! Hope he feels better soon.