Am I using "rainbow baby" correctly

I have a kind of dumb question.. this will be our fourth pregnancy but the farthest I have made it along, 8 weeks. When I first read term Rainbow Baby I immediately burst in tears and fell in love with it(everything is emotional or just psychotic with me right now 😂). I will be I guess you could say blunt with my question.. is it too soon to use Rainbow Baby? With my past experiences I know that I am still in the first trimester and the risk of miscarriage is high.