Painting dilemma (long). What would you do?

Watch several videos on utube. I like learn auto paint. Tony is trying to sale you to purchase his program, which is good, but you don't need to purchase to watch several videos and gain more knowledge. If you have the car in primer and want to see if it is smooth and straight, you can spray a different color primer over it. Spray lightly, not full coverage, now use the longest hand sander you have and sand the primer first in one direction and then in the other so you are crisscrossing to get a smooth surface. You have already learned a lot from the mistakes you have made, I know professional painters are good and really make a car stand out, but you can do a good job yourself. It is time consuming, but watch some videos, take your time, and most importantly, practice on the door you have. Make sure you have the settings correct and the paint mixed correctly.