Well I guess there is a difference to self teaching and formal education.
Self teaching will teach you things like real world tools, you will get into making stuff right away. Its like starting in the middle and slowly filling everything out.
In formal education they can be really slow to get into the actual fun programming or creation stuff. However they are good at teaching the reasons behind doing things, also importantly how to make good documentation.
Unless you make some really good games by yourself I would think you would have a lot of trouble getting a job in the field. As a hobby though there isn't really a problem

However before making anything I would strongly suggest having a design document. It can be simple, it just really needs to explain the concept of the game, what you want it to do and how you want to implement it. Relevant concept art or pictures, menu screen appearance, game controls, etc should be included.
Even as a hobby a design document is extremely useful, it helps you keep the game on focus and stops you losing sight of the big picture. This document can be by hand or typed really, as long is it describes the goal and presentation of your game.
Also you will probably need to make custom art for your game eventually, knowing how to do this would be very helpful.
I can't help with any software, don't use game making programs myself but I hope this advice helps

It's just a hobby. I don't want to go to school for a hobby.