I’m a D3 freshman still adapting to a new training plan. In high school I ran about 25 miles per week and now in my first year of college 60-70. So far, I have not done enough speed compared to high school. The team has been doing mile repeats at goal pace which I hit 5x1 mile in 4:59-5:02 with 3 minutes jogging rest. So far, I have run 26 flat on a pretty flat course.
Also, I’ve been struggling with my diet but personally find that fast food makes me feel better and perform better in practice?
Absolute zero/10
Pretty simple formula: Listen to your coach, easy days easy, don’t race workouts, look for improvement in small intervals.
Actually serious buddy
It usually takes a little time for your body to catch up to the new distance. It might happen at the end of the season, or next season, but it sounds like you're on the right track. Diet doesn't really matter as long as your weight is stable. Weigh yourself once a week if you're worried you're eating too much crap.
Just buy in and see what happens -- I've seen freshmen coming off low volume HS training drop from 27:00 to 25:30 in a season.
Stick to your 60mpw, keep up your supplemental work (strides, hill sprints, etc). Maintain whatever diet works for you, but try and transition to make it healthy. At this point it's fairly late in the season though so maybe stick to your routine.