My dear one,
It's unbelievable that you didn’t die; you could be dead now. You took life for sentient beings, to free them from suffering and bring them to enlightenment. You should rejoice that you have purified so much negative karma, therefore rejoice!
Please read the Amitayus Long Life Sutra (Tse do) 700 times.
Before each session, you should recite the following mantra to multiply the effect:
TADYATHA OM DHARE DHARE BENDHARE SVAHA
Recite the names of the Thirty-five Confession Buddhas 115 times every day. If you can, do prostrations with the recitation; that is very good. Do this for eleven days. Visualize well and at the end think you are completely purified.
Also, it’s good as a Dharma practitioner to think every day, every hour, every minute, “I am going to die.”
With love and prayers …