You have received negative feedback and you are justifying yourself, which is perfectly alright. You haven't done anything wrong anyways. Someone just had an idea that could help you do stuff better. But no one said that you should have invested more time. You should merely have spent it more effectively. But you know that now even without someone telling you, I suppose, with so little of what you had planned accomplished.
You set your own asks and demands for yourself, those which you have not accomplished. When someone asks and demands about the same, you say that you are not quite sure what's with all the asking and demanding. Maybe you should have set more realistic asks and demands for yourself, and then you would understand.
Can someone lock this thread, please? My question has been answered and I thank @Shizune and @Treewyrm for that, but this has a good potential to evolve into something that would revive the Skype chats.