Loss of appetite

I'm 4'11 and about 96 lbs. I'm 18. And according to the like test and things I'm not underweight. Anyway I usually eat a lot and frequently throughout the day. The only meal I wouldn't eat regularly is breakfast. (I hate breakfast) anyway for the past week, my period started on Wednesday ended today, I haven't been eating dinner or lunch or breakfast. And I don't feel hungry. I'll eat a snack around 8pm while I'm at work but won't want to eat once I get home. I'm not sure what I'm looking for here but has anyone gone through this? Is this just a phase? Because I usually eat a lot and on the healthier side.