Lately I have been learning Ruby because I felt limited by Construct and other game making engines. I am familiar with some programming concepts and game design, however I couldn't program past "Hello world!" before. Now I'm developing a would-be-roguelike and learning a great deal about game development as well. Granted, there were many snags on the way, but I've had professional help to nudge me into the right direction. Also the Computer Science classes many a year ago may have helped with the foundation, but well, that was in Oberon and programs were pretty much about typing text or outputting results of some math stuff.
You, too, can learn to program or, more accurately, script if you devote some of your time and mind to it. Sometimes I still wake up in middle of a night with an epiphany regarding to my little project.
The only limit is your own will and commitment. I've read stories about people who finally acquired driving licence after hundreds of failed tests. I'm sure I, too, will eventually succeed if I keep climbing back into the saddle.
Bottom line: It all depends on how much effort you are willing to put in.