When the pain feels too heavy

I've been looking after a stray kitten lately – such a sweet little soul. This morning I found it had passed away. After checking the security footage, I saw it was attacked by a dog. The very same day, my own cat passed away suddenly, likely from liver failure. And just last month, I lost my beloved cat as well, even though I made sincere du'a for her, asking Allah SWT for her recovery. I know our human struggles are often described as tests, with wisdom behind them. But what about animals? Why do they experience such suffering? Why wasn't mercy shown to them? The way the kitten was attacked was so violent... I can't erase those images from my mind. Right now, my heart feels heavy and confused. Instead of feeling closeness to Allah SWT, I feel distant and shaken. I'm questioning things I never questioned before. My imaan feels weak – weaker than ever – and I feel guilty for even having these doubts. I used to feel so firm in my faith. I don't know what's happening to me right now. May Allah SWT guide us all and grant us understanding.