Personally, I think you should have gotten more educated BEFORE you started taking 750mg/week. But that's done.
Top of normal range is usually about 1000-1100 ng/dl for testosterone. 800 is probably a good high average for a clean person. My natural level was about 600. Bottom of normal range is about 270 so 800 is really pretty high. I am surprised that at 750mg/week your level is only 1400. I'd think it would be more like 10,000ng/dl. In any case, you can most definitely grow big on 750mg/week. You can grow on 800ng/dl too it would just take a lot longer.
Don't confuse mg/wk and ng/dl.