Imo, i think you describe the situations and stuff too much but you didn't include anything on how you FEEL. I reckon try to add more emotion into it. Fear, agony, hopelessness etc.
"This place was so strange to me. Creatures would gather and press themselves against the glass – banging, shouting, screaming. I hated these walls. These walls, this place was keeping me from my home, it was making me sad and alone.
“Come one, Come all!! See Meeko the performing Orca” One creature would shout, whilst making me beg and perform for every scrap of food. The other creatures would laugh and shout with joy, they had enjoyed every minute of my misery."
You say it made you feel "sad", "alone" and your "misery". I don't think you should just say it straight out. Describe how you feel so the audience can interpret that you feel sad, alone etc etc.
Hope i helped. Good luck