Suicide Attempt of Loved One

Sometime early Saturday morning my fish, Alpha, attempted suicide. I awoke and stumbled to kitchen for coffee late Saturday morning and vaguely saw some strange blog lying on my freshly vacuumed carpet. Ignored it and began to move about kitchen. Glanced up to check on Alpha and realized he was not in his bowl. I rushed around to carpet and saw he had plunged from his bowl to the carpet below. He was lying very still. When I gently touched him he thrashed about. I grabbed him up with a paper towel and stuffed him back in his bowl. I have no idea how long he was lying on the floor, or what could have been so bad about his life to result in a suicide attempt but I'm concerned. Alpha seems particulary senstive to my absence and I was on vacation with W in Padre. Last time I was gone for 4 days he refused to eat for his sitter. He is swimming well and eating again. I am concerned that I did not see any signs...or if there were any I didn't pay attention. How could I have been so blind?