By this time Paul is probably a bit jumpy or gun-shy. In most every city during his journey he has been persecuted, stoned, beaten, sick, imprisoned, threatened, ridiculed, rejected, and slandered. Being human like us, Paul probably expected more of the same.
We all get that way a times. Eeyore!
We keep glancing over our shoulder looking for trouble to overtake us or walk through life anticipating something bad to come around the corner.
We get used to looking down, looking around, and looking within instead of looking up!
Acts 18:9-11