@dotUser
Normally, we'd recommend a site inspection, and while they can be a bit expensive, at the end of the day you're the only person who can put a price on the health of your haunted home.

That said: Reverse crawls are more common south of the equator, but not unheard of. So long as the crawling pace seems regular and the surface is tacky to the touch you should be fine.

A slightly sticky haunted wall is like a dog's cold nose: a sign of good health.