I was a vegetarian (included dairy) in high school, 6'0, 143 lbs then, but none of the fluctuations you are undergoing. Ran OK but often broke down all through college (PRs 10:00 2 mile, 2:38 marathon). By mid-twenties having all kinds of issues related to my diet. By 30 I had to quit grains and sugar and started eating healthy fats and meats. This kept me out of the hospital. Went on to become a world-class masters in my 40's with even better results in another sport requiring upper body strength, despite my lack of younger athletic talent.
It's all about balance. You do not appear to be in balance, with wildly fluctuating growth, fitness and weight, yet despite your inexperience in this area, you stubbornly refuse to listen to those with much wider experience. Good luck but your future does not look good on this path. Most of the profiles like yours are young women (with an unhappy ending), but eating disorders are a problem for guys too. You need to keep educating yourself with a more open mind and with stronger guidance. I can't imagine what your parents must think at this point.