afterlife signs?

My sympathy on your loss.. but, IMHO, never.

Deal with your loss and the reality that the possibility of an afterlife can only be determined after you die.

How soon? Just about immediately. There are those who received a sign, or a perceived sign, moments after a loved one ceased being earthly and others who have waited days, weeks months or years. It will depend on many things including your ability to receive and the soul of the departed to transmit.