Hi,
Welcome to health care magic,
Food poisoning is nothing but acute
gastroenteritis due to toxins of contaminated food from infections like bacteria or virus or parasite etc.
Symptoms usually starts after 12 to 24 hours of eating,like nausea,vomiting,
abdominal pain,loose motions,fever,weakness,fatigue, headache,abdominal cramps due to water and
electrolyte imbalance.
As per your symptoms like stomach pain,nausea you might have this gastroenteritis or
acute gastritis.
You should do some routine blood work,urinalysis and ultrasound abdomen.For that,you must consult local doctor who can examine you and order above investigations.
You will require antibiotics, antispasmodics, antiemetics,probiotics and other supportive treatment as per your symptoms.
So,consult physician for proper treatment.