Fogging Lacquer

I tried using automotive lacquer (Dupli-Color) for the first time and was wondering if anyone else has experienced the problem I came up with. I finished the preparation of the plastic, washed it good and primed it. I then wet sanded the primer to a slick finish. I had the first couple of coats of paint on with no problem and was getting the beginning of a deep gloss finish. I had to put the subject aside for a couple of days and figured the extra dry time before putting on some good wet coats would do the subject some good. When I began the application of the next wet coat of paint, I noticed that the finish was beginning to fog. Should I have not waited that long between coats of paint or am I dealing with a different problem such as humidity?