So i have been haveing weird pains in my lower stomach. could i be pregnate?

i have been haveing every weird pains in my lower stomach. iam a good eater but for the past month i havent been eating i feel hungry then i take a fue bites and am too full to eat anymore. i walk around feeling full all day even with out eating. i also have been every sleepy i feel real sick because i have the stomach pain,headaches and feel like im going to throw up but i dont. i just got off my period a week and a half ago so im sure im not prego. but im not sure what could be wrong wit me i need help asap i have no money to go to the dr and have no incurance so i just have to deal with it. im just looking for some answers on why is my body going crazy on me?