Poetry / Three Hovering Doormen--Four sonnets forming one poem [2]

In my English course we are studying Shakespeare. As a writing assignment, we are all supposed to write a poem using the meter and rhyme scheme of Iambic Pentameter. Our instructor says she doesn't mind it if the accents aren't metered.

This is my first attempt at writing sonnets, so any sort of feedback is much appreciated. Are there any stretched rhymes? Did I use language poetically? Is the content and vocabulary of advanced level?

Grief quietly slips into the next seat.
"I am back again," he needlessly sneers.
My weary, sorrow-filled eyes are his meat.
His poisonous fingers stop my scared ears.

I urgently glance for a leaving bus.
Hollow footsteps echo through the station.
"Even the wet cement knows it's just us."
My stomach churns in anticipation.

Silence slices fear through smothering air.
Dark and heavy iron gates creak and roar.
Wind fiercely winds up my strangling hair.
Anguish is an irrational downpour.

"I'll see you at home," Grief sizzles again.
"I am one of three hovering doormen."

Loneliness is column-like, still and gray.
A graceful tear slides down her trembling side.
Each bead of moisture is filled with dismay.
Tender tears slap hard concrete, pain I hide.

Lonesomeness twinges in my broken heart.
She knowingly stands there in solitude.
She whispers, "Is this tearing you apart?"
A cello intones a mournful etude.

While music hangs, Loneliness sobs a stream.
Standing on the bench, it begins to quake.
This incessant wailing was all a scheme.
The river has now flowed into a lake.

Loneliness' tear-pool rises 'round her.
And she quickly drowns in her painful whimper.

Depression slowly creeps up behind me.
His dark brown hands crawl down my anxious neck.
He heaves my soul from my kundalini.
At last, a small bus arrives, a far speck.

I try to run, but Depression holds firm.
Exhaustion pervades my aching rib bones.
This pain is expected to last long-term.
The once-hopeful bus, now full, gasps and groans.

A nearby white rose promptly collapses.
My shaking fingers touch its naive petals.
Depression's black dreadlocks are ashes.
This dust scalds like the fire of devils.

Depression tugs a trowel from his case.
He cruelly digs a large void in my grace.

While struggling to stand, Grief reappears.
Depression whirls around to face brutal Grief.
These unfriendly visitors bring my tears.
Wind wildly shrieks in, and is not brief.

This torturous storm drenches me to the skin.
Waves of sorrow violently bellow.
I know it's only started to begin.
A melancholy note falls from the cello.

The tall gates are a penitentiary.
Looming high, its shadow is ominous.
My spirit is choking in misery.
This suffocating tempest is heinous.

Grief and Depression choose to reminisce.
They merely talk while I drown in this abyss.