Also, all the "research" I have done has said that not only is it not harmful to let roots reach capacity before transplanting, it's actually beneficial. Starting your plants in a big pot just makes the roots go every which way and they never develop the tight, dense root structure that soaks up nutrients like a sponge. I go from rooting cubes, to Solo cups, to 1 gallon pots, and finish in 3.7 gallon pots. The tap root will basically go as deep as it can right away, but that's not necessarily a good thing. Obviously you don't want root lock, that's an extreme, but root density is a good thing for sure.
Your doing fine. I don't see any harm in trying. And I certainly don't see the point in being discouraging and telling you that you don't know what you're doing... but yes research is good and you've found a great place to start. Good luck.