What could this mean? Any docters on here??!?

Latley I ain't been feelin or actin like myself. I can't stop eating and I am always craving food. I have also been gettin dizzy all of the time. Plus have been reli stressy and even the smallest things make me upset. If I argue with my mum and bf it never used 2 bother me but all I do now is cry 4 ages. Wot could all these things mean??!