I found some reading about game development recently that changes all my process of thinking and development that help a lot.
Before, I just start building with an ideia in head and goal, press the time and hours to have results in the predicted time, and get sad when it didnt work ( never worked really ), what is frustrating because it works in any other dev area.
This new way of working has 2 main phases :
Phase1: Alpha
1) Start your project focusing in a "Alpha demo phase" stage of the game, this is your goal, to make a general ideia of your game, with the basic feeling of playing and basic mechanics, to work fine enough for you to say, ok, thats good and its a project.
2) The time you will spend in this is not important, and it can be very small like a day, or years, it depends of what you want to do.
2) In this phase, you dont put a time goal, you take any time you want, and it should not block you from trying to make another projects, meaning if you do this, you probably will have several "started projects" that is just waiting to continue when you decide to do it, and lots of abandoned idea/projects.
3) Also means that you may abandon most of those projects because you didnt get satisfied with the results, or performance was not ok, or it was too hard to do, too much time consuming, etc
4) But, once you get this demo working, then you start phase 2.
Phase2: Commitment
1) On Phase 2, now its different, you need to plan a project much like any other, with prediction on what you want to implement with time and effort factors, you already have your game, the ideia already works, so now you just need to add content, like maps, game modes, polishiment, etc. The idea is that in this phase the game is alive now, and you need to plan what you will do in sequence ( or parallel if in team ), how may days/hours for each task for all the content you plan to add.
2) Its important to be professional here, to avoid adding more than you plan at start or keeping content behind because you dont have time etc.
3) Polishiment is important in this phase, and I could not decide yet if its possible to have a factor for different kind of games, but I am currently using 50% of the time on phase2 for polishnment.
I found that working that way to be much less stressful and get better results. There are a lot of reading about this process of thinking also.
Another thing is that, game dev should not be your main source of leaving if you are starting, otherwise it will be very frustating since the income will be low.
One thing that makes this process necessary is that game dev is not dev, the dev word is misleading actually because most games are, in some cases 90% art and not developnment, its very hard to find a game that has less time/effort in art then dev, and it requires much more art thinking then programming or computer understanding, and mixing those completely different ways of thinking/work is hard.