Online courses may be helpful, but I recommend applying for a junior development position and seeking immediate employment. Professional experience will impart far more technical knowledge than coursework.
I'm not in computational work as a dev, but I would argue that coursework and the how things work in the professional world are two different ballgames. Jumping into the deep-end isn't always bad advice =)
I also agree with you at the same time. Just playing devil's advocate!
I suggest taking a few courses first to see if you like development.