my first question is that are u a frequent outside eater, meaning having hotel or canteen food, if so u have to be evaluated for H.pylori infection, dont worry it is a simple bacteria which causes overt gastritis
to make it very easily understandable. second thing i wud like u to get evaluated with an ultrasound
abdomen or even an upper GI endoscopy
. weight loss
is quite significant and wud suggest u that u see a doctor as soon as possible because general physical examination can rule out many things.