First, you regretfully used the wrong brand of paint. Behr is in my opinion the worst paint on the market. I have had many problems with the paint and its coloration.
Latex paint is wonderful, but it has areas that the painter must conform to and the weather must conform to also.
Latex, takes 24 hours to cure. Not dry, but cure out. If you paint in the noon or afternoon time and the paint seems dry in an hour or so, it is not. The critical time for drying or curing comes in the next 12 hours. If it gets cool, if mist occurs, if humidity gets high, or you have fog, your job will start flashing or in other words self detoriation.
Always paint with latex in the early mornings and when you are sure the weather at night will be acceptable to the paint.
In my opinion, your results was due to: inferior paint, and weather conditions that are not the fault of the paint manufacturer.
get a good brand of paint from a paint dealer and start over. Take a power washer to that Behr and wash that away.