You already said that. I am getting bored. So far we have two people in a nameless city. we don’t know how old they are, what they look like, where this city is located - could be London, could be Alpha Centauri - what time period this is etc. You haven’t grounded us or given us any details, which I why I am not feeling the connection with the narrative. I don’t care about these two people. You have to make me care so I would be interested in their survival.
This was insane; the radio promised sanctuary, but it was madness to believe such existed here.
His muscles screamed in protest
Muscles up and down his body
Stimulus response relationship is reversed here. First, there is stimulus, in this case clattering of the cans, then there is response. Involuntary response is first, cringing, jerking, jumping, yelling. Then come thoughts and only then conscious speech. In this case you have clattering, then response, than back to clattering. Separate these for dramatic effect.
Behind them something clattered in the alley.
Joshua spun around/held completely still/ etc. (Some sort of reaction here. Presumably he looks in the direction of the sound, so show us what he sees.)
The alley lay empty. The lone metal garbage can lay on its side. Something moved within it.
He held his breath.
A brown muzzle emerged, followed by droopy dog ears. Just a local stray scrounging in the garbage for a meager meal.
Note paragraph structure here. You are walking the reader down the ladder trying to build tension. Action. Reaction. New action, new reaction.
The clattering of a metal garbage can startled Joshua as it echoed down the alley behind them.
Trying too hard. Less purple prose, more to the point. Joshua glanced at Sarah. Worry churned in his chest.
Joshua glanced Sarah’s way, worry churning in his chest like a nest of raging serpents.
