Experiencing a loss of appetite since coming to college?

I’m originally from the South, in a suburban household with a pantry filled with nothing but junk. It would make sense that I was about 20–25 pounds overweight (my weight would often fluctuate within those five pounds). Just this year, I started college in New York City, where I’m walking more than I ever have in my entire life, but not exercising at all other than that.

I’d like to take this moment to say that I’m not depressed or worried about my weight in any way. I’m the happiest I’ve ever been, having made some of the best friends I’ve ever had, and I haven’t even missed home once. College feels like home to me and I literally could not be happier at this moment in time. And while I’ll acknowledge that I’m a bit overweight, I don’t always look it, and I can appreciate the pros and cons of my body like everyone else. I often look in the mirror and and pleasantly surprised- no warped sense of weight here.

But something’s changed since coming to school. I’m eating less than I ever have. You’d think with the more active/stressful lifestyle, I’d be eating more, but no. Back home, I’d eat two meals with TONS of snacks in between. Never had time for breakfast. Because of that, I’m not in the habit of eating breakfast now, and sometimes, I’ll only eat once a day. Sometimes that one meal is a smoothie and a bag of chips. And I’m good. I’ll get a personal pizza at the dining hall and only finish one slice. A lot of times, I’d just eat cereal and fruit for meals, since I’m a picky eater and dining hall food is so bad. I don’t know why, but I just fill up so quickly now. And I don’t get as hungry as often. It’s 4 pm now, and I have yet to eat anything more than a bag of chips, and six oreos, and I’m not even hungry. Oh yeah- and I woke up at six am today!

Smoothies are really the only thing I can bear to eat anymore, since to get anything else would be a waste of my meal plan. At least I finish the smoothies. I’ve lost weight too- ten to fifteen pounds, depending on what starting weight you choose. Though my weight fluctuated in the past, every time I’ve weighed it recently, it’s stayed the same, which is good, I guess? I really can’t eat much at all. I start feeling sick before long. It’s enough that my friends have noticed it. They’ll get angry at me and say, “You haven’t eaten anything, how can you be full?!” I lie and explain it away with my height- I’m not quite five feet tall.

I just want to know if maybe something could be wrong with me? It’s not natural to eat so little, is it? I’ve also recently started exercising once a week. Not very intensive, but I don’t want to worry about accidentally fainting in the middle of practice (it’s a club sport). I’ve tried to eat more, but I literally feel like I will vomit if I take another bite. Eating two slices of pizza is an all-out war nowadays.

Sorry this is so long, but I wanted to add as much detail as possible. Tl;dr: I can’t eat nearly as much as I used to, sometimes only once a day and want to make sure I’m not dying.