TW; Sudden Passing of my Cat

Another TW: It's described somewhat I just want help and support

!My baby of nearly 8 years passed away suddenly 2 hours ago. He was acting normal and I picked him up and his arms went stiff and he meowed loudly once before going limp and passing. I fully believe it was my fault, that I maybe hurt his spine or lungs or something. I pick him up all the time I can’t understand what went wrong this time. I just feel horrible I don’t even have enough money to cremate him and I’m not allowed to bury him in my yard I don’t know what to do. His brother doesn’t seem to understand what happened. Are there any reasons this could have happened? The only medical issue I know he had was asthma!<