can't eat?

Leah • always try and be happy, no matter what the circumstances
Okay like for about 3 days, I haven't been able to eat a lot at all, like I can eat maybe a few bites of something, and that's pretty much it. Like I can't eat a cheese stick or an orange like anything light either, and heavy meals won't work. Today I thought I was hungry, went into the lunch line, and didn't buy anything because I wasn't hungry. Is this a bad sign? I don't have a eating disorder Bc before this, I ate a lot tbh. Any advice or clue to what it is?