Scirra Construct 2 already take care of many aspects for makings games, "sound manager, 2Dbox physics, Facebook Integration etc..." game engines are made to shortcut/support you to make games, making thing from scratch requiring knowledge, patience and time, also if you are new to game development in general, i highly recommend you to start out with D&D tools, this his 3 benefits:
1- you will make your game in short time (productive).
2- you also learning programing/game development in indirect way
3- the most important part in your life, you will determine yourself if you interested in game developments or not, without too much sacrifices, like learning programing or other complex frameworks.
trust me you wont waste your time with Construct 2