Food help???

Once i've eaten i get hungry afterwards... Its weird because i have like a meal at dinner (i'm a veggo) Say like last night i had pasta and salad, about 15 minutes later i was really hungry again.. Somenody know whats wrong with me?? I'm not fat i'm 54 kgs. i'm not some food deprieved twig aswell as far as im concerned im a good eater, But i just want to know why i'm so hungry after i eat!. aswell i get food at night... It's weird?