When you say "I had it coming", does it always mean "I caused it to happen to me"? Can it also mean in an appropriate context "it just happened to me"?
Also, does it always have to be "coming" and not base form "come" like "I had it come"?
To have something coming is an idiom meaning that you deserved something. E.g.,
My wife left me yesterday. I had it coming because I had an affair with her sister, and she found out about it.