5 gallon vs 2 gallon fabric pot?

No, As long as you keep on top of her and give her what she needs when she needs it it will be good. You can expect her to be more difficult since she does not have as much of a root system. The pot will dry out quicker so more watering. More picky with nutrients because there are less roots to absorb them, but to much and you will burn the roots. In the end you should be fine. People have grown full size auto's in solo cup's so having 2 gallon's wont be that bad. Happy Growing.