You asked:
1. Do you get alot of girth from new veins or do the existing veins get thicker?
The vein growth is probably not going to add a whole lot to measured girth. If you measure, for example, with a piece of string, you’ll compress them a bit in your measuring.
There are several advantages to vein development, imo.
A veiny dick offers additional stimulation to a partner during sex.
Improving vascular function (as evidenced by vein/artery growth) is a plus in itself: more frequent and firmer erections because of better blood flow. Since you already have a degree of ED, this will be a major benefit to you.
Did any of your doctors suggest 25 mg of Viagra each night at bedtime? This will usually cause a sharp improvement in your nocturnal erection pattern. The average healthy guy has 4 - 5 of these a night, lasting about 30 min. each. It’s these events that give penises their real vascular workout. You might not need injectible vasodilators if V does the work for you.
Everybody doesn’t agree, but I think a veinier dick looks a lot more powerful than a smooth one.
2. and 3.
You are getting more tingling and burning sensations than most people report. You may be overdoing something. I don’t see anything wrong with mild tingling, but burning is definitely an indication that you are doing too much of something.
4. Haven’t really noticed any erection length or girth improvement, will this come in time and how long?
You’ve only been pumping a few weeks. Still early to see much if any erect increase, except perhaps while you are in the tube.
5. I know nothing about ADS use.
6. Stretching while pumping: you mean by pulling up on the tube while under pressure? I do this from time to time. Don’t know if it helps or not but I think you’ll get your best stretches not pumping: manual stretches and jelking.
7. I’ve never wrapped while pumping. I do (about half the time) use a flexible cock ring. This gives more girth, at least while under pressure.