Reasons for sudden loss of appetite?

The heck is wrong with me? I normally eat like a pig, but for the last few days I've had to force myself to eat. I doubt I've had over 1000 calories in any of these given days (and yesterday I highly doubt I met 400 calories). I don't have any known medical conditions.

What do you think it could be?
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+1 y
I don't feel particularly stressed. The first day or two, I blamed it on my new boyfriend because he was giving me butterflies so bad I wasn't hungry (ew, corny). But it shouldn't be sticking around this long.
Reasons for sudden loss of appetite?
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