well it does sound like a great idea to go on to grad school. it is difficult to go back once you leave. but that is going to be challenging coming up with your specialty in such a short time. i think if you enjoy programming and that is all that stands out for you right now it may be the best choice. the passion may come when you have gotten more into your studies. there isn't anything to say once you have gotten your degree and are working in the field that you cant do other things or take more classes so you can switch to other subfields,. good luck